Get Your Dog Care Questions Answered by Experts
If you want to help the dog, you need to do the blood work. If you simply cannot afford it, you need to talk with the vet about euthanasia so that the pet will not suffer.
I would return to the vet tomorrow to rule out the idea that this may be an allergic reaction to something. If this is the case, you might be able to give him an antihistamine or steroids to help.
At this age, this dog should be healthy and happy even if he is deaf. I would go ahead and have the bloodwork done. You can ask that they only do specific tests so that your bill might be lower.
Let me know if you have more specific questions. I fear that my answer is a little too broad.