Preparing an answer now.
I am sorry to hear about this concern for Bradley.
A few points to address:
1. Pancreatitis. If your vet is trying to diagnose pancreatitis off a regular blood test just using amylase and lipase pancreatic enzymes, that is not accurate at all. There is more specific testing that could be done that is far more accurate but can take a few days to get results.
2. Even if not pancreatitis, clearly Bradley is not doing very well. I have to assume the kidneys and liver are fine if they didn't mention any bloodwork changes for those organs to you.
3. Next testing that should be considered is an abdominal ultrasound. That would be great for checking the organs and a look at the pancreas, and it is non-invasive.
If going down hill, he will need to be hospitalized again. It is possible to manage pain at home. Vets will commonly prescribe the injectable pain medication called buprenorphine, which can be given orally in very small amounts. Very effective.
Also, a vet can teach you to give fluids under the skin (subcutaneously) at home. It is not quite as good as IV fluids, but it definitely can help prevent dehydration.
If he has been vomiting, ask the vet about a medication called Cerenia. It's a once a day anti-vomiting drug.
Also, if not eating or vomiting, its okay to give the antacid called Pepcid A.C. antacid. You give a cat 1/4 tablet of a regular strength 10mg tablet every 12 hours to help with stomach upset and nausea.
Wish I could do more, but hope that information helps
You are welcome. Sorry for the tough situation.
My gut tells me that even if pancreatitis is a problem, it is not the only issue, at this age, contributing to the illness. So, a second opinion will be well worth it.