First off, the Tampa mob had its hand in Cuban politics since Ignazio Antinori in the mid 1930s, due to the large Cuban population in Tampa and ties on the island. Cocaine was flowing from Cuba into to Port of Tampa even earlier, in the 1920s.

Point is, pre-Castro Cuba didn't revolve solely around Lansky/Luciano.

Since the Mafia were bankrolling Castro as well as Batista, I wonder if there would have been any fallout in the mob's relationship with Batista going forward.

A Cuba without Castro would have spurred more casino growth, which may have impacted the viability of Las Vegas