I wonder how it works also. I think it is an age old situation. We may agree in one life and disagree in another. Who is your lord is the question and if your way psychic you can recieve an answer.

I heard that Lucifer cannot incarnate again, that his soul was obliterated but he isn't the only one.

Hitler was a student of Askar, as I heard it. Askar has not done enough damage to be obliterated. So karmically speaking you have a long ways to go before "the karmic commission" or whatever higher authorities step in.