Looking at your posting here, especially about the Jews in the Warsaw Ghetto, I was reminded of John Hersey's Book The Wall. A novel, but one that was fairly well researched.
I don't think anybody's about to let the nazis off the hook for that one.
As for something changing your mind about how the Jews reacted to the Warsaw Ghetto when you found out that Jews helped with the roundup, I'm unsure I follow. Any suffering I've done in my own life hasn't exempted me from to foolishness in my own life, nor has it granted me any nobility of character. If I'm lucky and I work at it, maybe I gain some empathy for the suffering of others and maybe maybe maybe the courage to do a little bit about it. I remain as staunch and pompous a fool as ever I was.
I wouldn't expect otherwise from the Jews or anybody else in Warsaw. Some folks did a little better, some didn't.
My understanding is that most of those Jews thought they were trying to make it easier for their fellows and doing something in a less draconian way than the S.S. would have done. I don't really know what I would have done in such a bind. One of my cousins, if I remember correctly, thought there was some hope for an actual resettlement eastward rather than being moved to death camps, but I'll tell you, I can't really be certain of it after all these years. And who knows how much people were fooling themselves? Not me.