I'm so sorry to hear what you and your son are going through. I would recommend having him re-assessed; it sounds to me as if the people he's been treated by so far hasn't been able to properly define the problem. Also, since the issue of attachment disorder has been brought up, and you've said it strongly resembles his behavior, maybe it would be a good idea to schedule an assessment with a professional who specializes in that field?
I really wish you all the best, and I hope you'll see some improvement soon.
