Just some brainstorming additionally, hope it may help or just give a hint.
Was just one "bump" removed? And this one was a chromatophoroma? The questions is... are the other bumps same tumors or different? Where are all these bumps located? Over here, there were some studies done about chromatophoroma in reptiles last year (HECKERS, AUPPERLE, RÜSCHOFF et al). They primarily searched for pigment building tumors in bearded dragons, but as far as I know there are only few studies about these tumors in reptiles at all. They wrote they often found melanophoroma (do you know which kind of chromatophoroma was found in your chameleon?) at the lizards' lateral abdomen and mention all chromatophoroma as potencially malign tumors, which recidivate and metastasize often. If there were metastases visibile in the x-rays yet, I'm sure your vet would have seen them. I can't say anything about the x-rays due to their small size.
Looking at the jaw problem, there are two things coming in my mind directly: Myositis, which would match the problems with all other muscles and not wanting to drink or eat, too. But if there was an inflammation inside his muscles, a differential haemogram would show increasing leucocytes. And you probably could notice sunken muscles in his casque and cheeks. At last, myositis in reptiles occur really seldom... I can't remember having heard of any described case in chameleons. Just mentioned as opportunity.
I would get x-rays from his head under general anesthesia to except another tumor affecting his jaw bones or muscles, which is another idea only thinking of the mouth opening problem. Same time, one could take a biopsy out of this mass inside his mouth. And additionally, your vet can examine your chameleon's mouth carefully under anesthesia. Sometimes it's really difficult to recognize lesions, masses or anything else inside a chameleon's mouth, especially as long as the chameleon is not willing to cooperate.
About the blood: I would always think about kidney issues causing the edema although the values were all right (not all, he had hyperphosphatemia). We only can see most values changing as soon as 75% of the kidneys are destroyed. Other causes might be heart failure (but I've only seen this as a reason in very few chameleons). The question ist whether the edema is caused by something in the jaw going on or is it an additional problem having nothing to do with the other problems. You mentioned CPK was increased: Might be caused by altered results, might even be caused by damages in heart muscle or skeleton muscle cells.
How old is Luie?
Unfortunately, I think your little guy does not only have one single problem.
Hope you will find out the reason for his problems with your vet soon.
