Re: all my opinion of course
What part, exactly? Moore has said THE KILLING JOKE isn't really "about" anything other than Batman and the Joker, but that's no reason to "repudiate" the story. After all, some think TKJ is about the nature of mental illness, part of the "Superheroes are crazy!" idea that continues to this day.
As far as crippling Barbara, I don't think Moore ever wrote any Batgirl stories.