I'm going to assume this is real, because there is nobody asking for money.
My answer is the same as everyone else's - you need to go find another vet. No matter how out in the middle of nowhere you are, I'm willing to bet you can find another vet less than two hours away. Yes, it sucks to have to drive so far and spend gas money. But there is nothing anyone on an internet site can tell you that is going to save such a sick dog. Pull out the yellow pages and look under vets - start calling. If there are no small animal vets, take a chance and call a large animal vet.