Sick Beardy

My 8 month old Beardie Linus has had a rough few weeks. Started out not eating for a week so I took him to the vet where she said he looked fairly healthy but recommended his lighting be updated to the Reptisun Power sun bulb and that his appetite should return in a week. She also found a mild case of cocydia and gave him a round of meds.
Flash forward four days later and I find my Beardie slaying on the floor of his habitat, eyes closed and barely responsive. I rushed him back to the vet where she suspected that his medication had caused his stomach to fold over on itself and it required surgery to fix. Once she had him on surgery, she couldn't find any problem with his stomach and his organs looks pretty healthy except that his liver was slightly discolored. Blood work was taken and sent off over the weekend and Linus spend 3 days at the vet in ICU. He slowly started to make improvements and the vet called me in to bring him home and review his blood work. She said that his blood work had a lot wrong with it very high white cell count and glucose levels which she thinks could be a rare stomach cancer or perhaps sepsis

He is only 8 months old and she hasn't seen cancer in any BDs that young.
He has been home for a couple days and has been enjoying his lamp. He has random moments of alertness and had a (runny) poo tonight.

He went into the vet today and got another antibiotic injection, which he gets every 72 hours. They said he was looking a lot better than when he left!

After work I came home and checked on him and he looked his usual but then I left for a while and came back and he was sleeping and his beard had turned very black And has been that way for a couple hours so now I'm worrying again.

When we left the vet the other day she said she didn't know how long he would live but that she didn't think it was time to euthanize. I just don't want him to be suffering. He has once more round of antibiotics on Sunday and we will check back in with the vet while we are there

I'm surprised the vet opted for surgery before a blood test. Did the blood test reveal a high white blood cell count indicating infection? If not, the antibiotics may be pretty harsh on the system and mild coccidia shouldn't be a huge issue on it's own. The high blood glucose is concerning and does often indicate a tumor based on what I've seen. I would offer him plenty of water by dripping it on his nose to lick up. I would also keep him warm and comfortable. Give him some fleece or other soft surface to lay on and keep the temps bumped a bit even overnight (shoot for around 80 or so).