Hey, I read some of the thread but not all of it. So If what I ask ha already been asked then I'm sorry. When you went to the vet idd they test for anything? URI, Parasites, kidney disease? Did they do x-rays? Also have you seen her drinking? Also what is the temp with that 75watt basking bulb? I use 40 and 60 watt house bulbs for my adult panthers here in the dead of winter and they keep it 85 when they are about 5 inches from the basking spot. 75 watts just seems really hott for a 4 month old veiled even if it's 6 inches away, but temps differ everywhere. Also have you tried lowering the overall temperature to see if the cham has heat exhaustion from being at a constant 80 with a basking spot that is probably 90ish? sorry I just want to help, I have seen alot of dehydrated chams/heat exhausted chams act similar except they move around very little. It's just a though. Hopefully you can find a better vet that will treat the underlying issue causeing the closing of the eyes because I suspect it is not just an eye problem is the cham can open them to shoot food and then closes them again. It's completely dark in the cage at night right?
Justin
EDIT: Sorry if I come off rude, I'm on my smoke break at work and didn't have time to read the whole thread but hopefully you little cham gets better.