Wait a sec, I must've missed something. Why the lawyer, at this point? What you are doing seems to be working. I would suggest waiting and playing that card later, if all else fails (remember, you only get to play that card once).
Going back to the living situation, the more I think about it, the more I think it would be better just to have him move back in, rather than moving to some nominally neutral location. To what purpose do you want him to separate himself from both of you? If you want to attach some strings, in order for him to prove himself a little, I would suggest requiring him to join you in seeing a MC, or perhaps going to a Retrouvaille weekend (I've never been, can't get my W to go, but I hear very good things about them). Just trying to put myself in his shoes (and I obviously don't know him like you do), I would think he might be more willing to do something like that, and it might be more productive.
