Dog Surrendering

I have tried every local shelter I can think of and no shelter will accept my dog since he's bit a dog and is shy. I cannot keep him as he's a danger to my other dogs. A rescue in California transported him here and refuse to take him back. They said nothing about his aggression and even lied and said he was great with all animals. He's a total sweetie when it comes to people he just takes a few minutes to warm up but I guess that makes him unable to be accepted at our local shelter. I dont want to put him down just cause he needs to be on his own but I'm having to either keep him in a kennel or in a room with me cause I'm always nervous about him being around the others. Does anyone know of any shelters that would take him that aren't on google? We're in the helena area so we can travel pretty much anywhere in the state in a reasonable amount of time.