Seems like the ball is in Minnie's court.
Women would naturally discuss details of intimacy and sexuality, so it doesn't seem out of the realm of reality that she would have to talk to someone about what he told her. Perhaps Minnie needs to know that it's okay to know about your experience as well, as far as you're concerned. It doesn't mean you know about what happened to him, just your wife. That might give him the necessary space.
I'm going through something similar with my brother and who knows what. I appreciate your posting this. It's good to just breathe the open air for a while.
Lose the drama; life is a poem.