This is b.s. Oswald didn't know Kennedy would be coming to Dallas, let alone his route, when he took the job at the Book Depository. It was a matter of looser being in the "right" place at the right time.
I used to be a big fan of JFK conspiracies. Now, I believe in the "lone loser" theory. I guess, in a way, one could tie in Castro, in that Oswald was a Castro-ite. But all that happened was that Oswald did Castro a favor.
If some lone loser took out Chavez, lots of people in the USA would probably drink a toast, but that would not necesarily mean that the USA (or Pat Robertson) had anything to do with it.