So your husband is still in contact with her?
As far as the OBS are you saying you spoke with him directly? As long as you got to tell him the truth what he does with it, you can't control. You can't make him care if he doesn't.
Are you divorcing? I'm confused what is going on. If you divorce you can certainly depose her if you want to. It's not up to your WH. However you might be able to negotiate a better than usual deal if you agree not to.
So what's going on?