How sad, this poor lil guy. When we first got Zander he thought he could chase the kitty, we taught him kitty chasing was off limits, so now they hang out and chat, they chase each other & do a little wresting but he is gentle. The lifting the leg, I think can be worked out too. So there, he is near perfect. I just can't believe the ill ways of some people. I bet she still has him but is trying to get $$. She knew you would have taken him back. Very sad.
Don't be hard on yourself, you didn't know the ill intentions of these people.
I hope you can locate him. Best to you.