There is still hope... If you know someone with a kennel (the more dogs the better) you can put him in a run right next to another dog. Heck, one on each side of him would probably be better. You basically have to desensitize him to the situation. Put a bark collar on him when he is in the run next to the other dog(s). This way when he gets worked up and starts growling/barking, he gets a correction. Leave them side by side for at least two weeks. Only get him out for excercise, training, and play time. Make him eat, sleep and live next to the other dogs. Then get 'em both out on lead and see how he does. I think you'll be surprised.