Adoptable Medium Spayed/NeuteredUp-to-date with routine shotshousetrained

We were told Hooch was “spoiled rotten” by his previous owner, a man who had to give him up when he needed hospice care. He came to us two months ago from a temporary home where he “played too rough with their Great Dane” and was covered in scratches, scars, punctures and tears. After receiving weeks of medical care these wounds healed and he was neutered and brought up to date on vaccines. He has a very negative/aggressive reaction to most everyone, except his current foster, when they come near his kennel or close to him when crated. He seems ok with most people outside of his kennel or crate but has not been socialized or allowed to get close to other people. He walks decently on a leash, usually sits when told, comes most of the time when called, like to ride in cars and will tolerate a muzzle pretty well. He becomes extremely agitated if you put a metal choke or prong collar on him. He show no food aggression with his foster and will play gently with her. He doesn’t seem to show aggression towards other dogs but knowing how chewed up he was, we have not put him with any. I don’t know his age. I don’t think he was ever socialized or trained.