Bolivar was a South American first and foremost. He was born in Caracas and fought throughout modern Venezuela, Colombia, Panama, Ecuador, Peru and as far south as Bolivia. His forays into the Caribbean were limited to Curacao, Jamaica and Haiti when he was in exile. You'd need a change where Bolivar would become more focused on the Caribbean and naval affairs than he was in OTL.
The opportunity might be when he was in Kingston, Jamaica in the latter half of 1815 trying to get British assistance for his campaign to liberate South America. If he wasn't so quick to accept the Venezuelan pirate Renato Beluche's offer to join the Republican community in exile in Haiti, and still survived the assasination attempt by his manservant, Bolivar might eventually end up with earlier British assistance, while his more prolonged correspondence with Caribbean merchants might give him more of an insight into the Spanish island colonies. If Bolivar gained British assistance before meeting with the other Republicans in Haiti, they might make the core of a force - alongside the British Legions - to try and take the Spanish island possessions to secure as a base before heading to South America. It might also weave them into a more cohesive force both militarily and politically, whereas in OTL they scattered once they returned to Venezuela and effectively became disunited warlords.
The problem is whether Bolivar would be accepted by those in the Caribbean islands. Their economies were heavily dependent on slavery and the slave trade, and Bolivar in OTL promised to free every slave in areas he occupied to Alexandre Pétion, first President of the Republic of Haiti, in return for money and supplies. Cuba was on the road to producing over a third of the world's sugar in 1860, booming economically over the agriculture on their fertile soil on the backs of tens of thousands of slaves imported to the island. In fact, landowners fleeing the slave revolt in Santo Domingo fled to Cuba, and they'd be extremely hostile to someone like Bolivar, with Haitian assistance, trying to liberate their island. The Haitians, alternatively, would be wary of Bolivar trying to take Santo Domingo, also on Hispaniola, to be part of his new country. Puerto Rico, OTOH, was the destination of immigrants loyal to the Spanish Crown fleeing other Spanish colonies that were rebelling, and they'd be extremely unwelcoming to Bolivar as well.
Unfortunately, for a variety of cirumstances, Bolivar's Gran Colombia would not be welcome in Spain's colonies in the Greater Antilles.