Dog viciously attacked, needs surgery

Today my dog Freddy was attacked by this huge dog, it grabbed my dogs neck and face and shook him around breaking his bone. I went to this emergency vet, it’s Sunday so this is the only one open, and it’s incredibly expensive. They told me his mandible is broken, which is his lower jaw and it’s hanging off, one side is completely off. Then he also tried to scratch off his jaw because he was in so much pain, he also got bit in his neck. They haven’t even given me price for surgery, but for stabilization alone they first told me roughly 2690 but then they came out again and gave me a second number of 4800, this is to genuinely stabilize him (?). Again I’m at a random clinic thats open on a Sunday. I already paid for some of what I could,  I put down most of my money to secure an apartment in LA, I also have to ship my car, etc. This is a large fund on me right now. Anything helps... I don’t wanna lose my dog.. I’ve had him since I was 8 years old.. Please, thank you.