Did Hitler escape to South America?
I am inclined to think that he didn't but the case is not as open and shut as you might imagine. Consider two things:
1). We only have the word of the Red Army for what they found in Hitler's bunker and the old Soviet apparatus told lies as easily as some people tell the truth. They even had a word for such lies: "Disinformation" -- with one of its more successful examples being the demonization of that great man of God, Pope Pius XII.
And it would have been a great disgrace for the Soviets if they had let Hitler slip through their fingers. So they would have claimed to have got him even if they had not -- reasoning quite cogently that Hitler would not blow the cover that they had conveniently provided for him.
2). It is undisputed that many Nazis, including some senior ones, DID escape to South America. So if them, why not the Leader himself? He would only have had to manage a night flight from somewhere in the Reich to Fascist Spain and all his troubles would be over. A transfer from there to one of the South American dictatorships could have been arranged in a variety of ways. And the Latin American elite were at that time (and to a considerable extent still are) apostles of Bolivarism -- which is just Fascism by another name, Fascism complete with a Fuehrerprinzip of course. So Hitler's welcome would have been warm, though secretive.
And a night flight would not even have been particularly dangerous. It would be assumed by all concerned that only Allied aircraft would be in the air by that time and the profile of some German military aircraft was similar to the profile of some Allied aircraft (e.g. the Junkers 88 could be mistaken for a Mosquito bomber) so any challenge would be unlikely.
But the reason I doubt that Hitler escaped is that I cannot see him ever shutting up for long. The man was a born preacher so I am sure that if he had survived we would have eventually heard something from him in some way.
But if you want to read an interesting article offering evidence that he escaped, see here or here