Most of those are Post-War knowledge projected backwards; case in point is that in July the Allies don't know any of that and are actually detecting the surge in German production, particularly among aircraft.
The Conquerors by Michael Beschloss is a good read on this, and with regards to the situation as of December of 1944:
Five days later, Hitler launched the counteroffensive soon known as the Battle of the Bulge. “A complete surprise to our people,” wrote McCloy in his diary. General Marshall gravely warned Stimson that if the counterattack succeeded and the Russians refused Anglo-American pleas for help, the United States would have to “recast the whole war,” retreat to the German border and let the American people “decide whether they wanted to go on with the war enough to raise the new armies which would be necessary to do it.”
If we are presuming the Germans don't do Mortain but utilize a river-line based defense, perhaps there is no opportunity for a Bulge like attack but if so then you've traded that for a dozen Hürtgen Forests from Normandy to the German border, which is absolutely going to inflict serious casualties upon the Anglo-American armies which will not be politically popular at all, especially in an election year in the United States. Early 1944 and late 1944 saw U.S. public opinion reach 40% for a peace deal IOTL even without serious defeats or costly victories (of the vein being discussed here) to match that; all you need is another 10% of the population to switch into the aforementioned column to get a majority.
Outside of the Anglo-American equation, Stalin is the definition of realpolitik and the fact he kept informal contacts into October of 1944 shows he was willing to keep his options open because he was already looking forward to the Post-War era. Cutting a deal with a Post-Hitler Germany gives him the option to extend his influence beyond what the Anglo-Americans are offering, in that he can be limited to the Elbe or, by restoring the 1939-1940 arrangement with Germany, he can have influence on the Rhine without further casualties and binding Germany to himself as the junior partner in a new alliance.
The battles in the Hutgen forest were a unique confluence of factors. The Allies were at the end of their logistics tether, the broad front strategy had stretched them out from the Channel to the Swiss Alps denying them a concentration of force, their inadequate replacement system meant that their frontline units were understrength and increasingly combat ineffective, the weather and terrain meant that their artillery and airpower was of limited value and they could not effectively use armor.
Meanwhile they were attacking into a hellish mixture of legacy fortifications from the Siegfried line, including bunkers, barbed wire and dragonsteeth all set in dense forest against a motely collection of German units that for the first time since the campaign began were operating on home soil with secure and adequate supply lines, large reinforcements including rebuilt and rearmed formations but also entirely fresh divisions and simple objective, hold the line. All this taking place in a horrific winter.
There was not a dozen places in Western Europe for this to happen. For a start if the plot is successful in killing Hitler and causing chaos Von Kluge is going to ask for an armistice with the Western Allies days before operation Cobra begins no idea how that goes but I guess they either refuse or demands he withdraws forces and starts disarming, if he fights the offensive probably starts as OTL and nothing he does is stopping it from smashing their positions in Normandy, they lack the reserves to do more than a fixed defense and once the allies break through anywhere there is nothing to plug the gap and as there is a coup going on involving most of the senior officers in the West its doubtful they will be particularly focused or coordinated on military matters when they are meant to be easing the transition and setting up negotiations.
Luttrich was ordered because Cobra ended the Germans ability to contain the allies as the front was now widening rapidly towards West towards Brittany and South towards central france and the Germans did not have the forces to defend either and hold the British most of their panzer divisions were already locked in bitter fighting against the British and Canadians. If its not launched at all then they continue to fight it out whilst trying to escape beyond the Seine.
The Germans however have several critical issues.
1. They are out of fuel, OTL this hindered the withdrawal against the British and hindered them in Falaise.
2. They are operating against Allied Air supremacy forcing only night movement or murderous retreats along a limited road network.
3. The Allies are moving faster and sweeping across Western France with an aim toward encircling Army Group B. The OTL offensive briefly paused this (for a few days before they regained the initiative) but without that they will be carrying on their own course, the Germans will not march blindly into the trap but their escape will still be difficult and many of the units OTL trapped in the pocket will probably ITTL be fighting a desperate rearguard.
4. The Allies have alternatives, Dragoon (decided on in July to ease the logistics burden and please the French will suddenly extend the frontline by hundreds of miles again. They will have the paratroopers again.
5. They have been already trying to stop the Allies with a fixed positional defense, and they slowed them down, even halted them in places but at the cost of gutting all their formations, draining their fuel reserves and leaving them no adequate reserves to respond to emergencies of which they faced multiple. Here they are going to be doing the same again but in less suitable terrain, over a wider front, against an enemy that enjoys superiority in firepower and manpower and can yet again launch multiple drives.
If the Germans fight it out in Northern France they may well just get destroyed there instead of in the West and if their retreat is less rapid than OTL then Eisenhower may not oblige them with the broad front strategy and instead focus on destroying or outflanking whatever army is in front of them. If they've been fighting a running battle in France the whole time by the time they arrive in Germany then they may well not have the forces that OTL blunted the allied drives because they will have been expended in those battles instead of being pulled together on the German border.
All the while this is happening Army Group Centre is being wiped out and the Eastern Front is in its most dire straits of the entire war from the German POV.
That's not really a situation for a dozen multi month long infantry slogging matches to occur, if the Germans are engaging in such defensive battles they'll be doing so without fortifications, a fixed front line and against armour and artillery and aircraft in exposed and hostile territory for the most part. We saw how that ended OTL because it destroyed the Army in the West. Also thanks to Ultra they will have a sound idea what the Germans will be trying to do so can make their plans accordingly.
You are very fixed on some polls about the American Public turning towards a significant minority wanting a negotiated peace in late 1944 after a setback. But by the time of the Bulge FDR is starting his fourth term and increased his congressional majority. They are the ones who decide if America stays in the war and they certainly didn't seem inclined to just give up for no reason OTL. Marshall may have lost his nerve briefly but he was a political manager thousands of miles away, the generals at the front decided within days of the OTL bulge that this was their chance to destroy the Germans, just like during Luttrich they decided this was their chance to destroy Army Group B and I'm certain if the Germans dig in on the Seine the Allies will immediately again grasp that this is their chance to fix the Germans in place and envelop and destroy them.
The plotters had no interest in negotiating with Stalin and Stalin himself knows the Allies are now advancing in France and Italy and he is currently boasting about taking 400,000 prisoners and clearing the way to Berlin. What do the Germans have to offer him that he won't have in months regardless? The Allies weren't counting on being handed an army group or two due to doomed offensives, this was the campaign they thought they would be waging and which the Germans did not actually believe they could wage successfully.
The Allies often had an incomplete grasp of what the Germans were doing but the Germans were far worse at guessing what the Allies were trying to do and this entire three month or so period is one of continuous crisis for them before the weather and logistics burden of the massive advances buy them a few months breathing room to rebuild for the bulge. The Germans would need to be somehow constantly locked in incredibly bloody conflict with the allies more or less on the Allied terms and also consistently winning and making all the right diplomatic deals and somehow not losing territory or resources despite aforementioned bloodletting.