Sheduck, hello and welcome to the forum. Your dad is making a very poor decision to continue drinking. The nurse was absolutely right. His liver enzymes and ammonia level are very high. He is going to die a slow, awful death if he continues drinking and nothing that is done will help him. In fact, the doctors will be less inclined to treat him knowing that it's a waste of time. What you have described is typical for end-stage liver disease, though it's impossible to say just how long he has left. I don't know what they are looking for with the ultrasound---possibly liver cancer.
If you have read some of the posts here, you know that others are going through what you are, so you will find a lot of support here.
Sheila, is he taking any pain meds yet? If not, that would be one good reason to follow through with x-rays and scans and see the doctor. There is no reason he should have to suffer. Also, if the doctor has a better idea of how severe his disease is, hospice could possibly be called in for "comfort care," which includes pain meds.
Sheduck, liver disease affects the kidneys, and if they are giving him diuretics they are also hard on the kidneys. He may be experiencing something called hepatorenal syndrome. If he has stomach ulcers, that could definitely make him physically intolerant to alcohol. Antabuse is a drug that is specifically given to alcoholics to try to keep them from drinking. If they drink while on it, they throw up. You need to find out what medications he is currently taking.
Being a diabetic can also cause kidney problems, so this is probably why he is not on diuretics--it would make an existing kidney problem even worse. He would be better off on an opiate such as Percocet than an antiinflammatory, which is also bad for the kidneys. I worked for a nephrologist (kidney specialist) who would have no problem writing Rxs for opiates but was very opposed to anti-inflammatories. I don't know if paracentesis (draining of the abdominal fluid) would be possible in his case.