That seems like a fairly useless part of consequential theory. In particular, when retrospecting about one's previous actions, a consequentialist should give more weight to the argument "yes, he turned out to become Hitler, but I didn't know that, and the prior probability of the person who took my parking space being Hitler is so low I would not have been justified in stabbing him for that reason" than "oh no, I've failed to stab Hitler". It's just a more productive thing to do, given that the next person who takes the consequentialist's parking space is probably not Stalin.

Real-life morality is tricky. But when playing a video game, I am a points consequentialist: I believe that the right thing to do in the video game is that which maximizes the amount of points I get at the end.

Suppose one of my options is randomly chosen to lead to losing the game. I analyze the options and choose the one that has the lowest probability of being chosen. Turns out, I was unlucky and lost the game. Does that make my choice any less the right one? I don't believe that it does.