I say, keep the dog and rehome the kids! Anyway, in seriousness, if there is any chance he would be put down, I would rehome him if at all possible. It is also a good idea to have the trainer call the rescue group. No wonder he did bite in the first place. Kids can be very hard on a dog and unless one is really understanding, I can really understand. Shame on those people for doing dogs like that. They don't need or deserve the love of a dog. Wish I could take him! I'd make up for those lonely times and spoil him rotten.