HELP! with my wolf hybrid rescue

I do rescue and have rescued several breeds but this is my first. I was called to a vet office on a "scary" wolf a few months back. He was hit by a truck and managed to live through that with his front leg dangling! he was finally picked up and still left unattened for the 3 day "waiting/claiming" period- long story short, when I went out to look at him I couldnt leave him there! Already loved enough to have been altered, but couldnt be claimed- its illegal in that city- so his leg was ampuated and between the horrible prior infection and few set backs, he is doing great... on that part! ok, my problem is, he is an indoor/outdoor guy now- house trained, the works- BUT he wouldnt eat much right after he started getting around... I took him in and they couldnt find anything. Heartworm neg- all bloodwork fine, but he wouldnt eat we tried everything. One night he threw up, A HOT PAD!!! I was devastated- I have dobes and we are a doggy family and now how things disappear, LOL- ok, thought is was a one time thing. He started eating great, doing awesome, BUT WE KEEP catching him trying to eat rags, towels, socks- its so weird. He looks for them! everything gets put up, we have rescues that come in and out and this is the first time in 8 yrs I had this happen! He can reach up to 7ft and open doors, he eats doggy toys- so we have to watch when the others play. what should I do! The vets have no clue, is he lacking something? I mean we have done many rescues and puppies, chewing, but this guy is gonna eat something and get hurt. You can dry your hands, put the towel on the counter and its gone! I am chasing after him to get it away, hes not playing, he eats it! HELP PLEASE! I know this is weird and I dont want negative feed back, we have really tried everything.