A variety is best. But you HAVE to gut load. And you HAVE dust them with the appropriate things. Crickets, dubias, superworms, hornworms, and the occasional wax worms. However he needs a vet first.
I can just mean he has something in his eye or that it's irritated however he could scratch his eye or get an infection doing that so you should keep an eye on it.
You'll want a linear uvb light so it covers more area. Mealworms are generally not okay for chameleons as they're harder to digest. Remover the wood chips. And you'll want to put his cage on something taller so he can be up high.
Three things it sounds like you need
1- gut load your crickets better
2- a multi vitamin for your chameleon
3- a new vet.
The vet you took your chameleon to should have asked you so many questions and pointed out what you were doing wrong. The fact that you only left with pain medicine is kind...
In my experience my little dripper usually lasted about ten hours. I'd use it only when I was gone and wouldn't refill it after returning home from work. Since I've gotten my mist king I've noticed no signs of dehydration and no longer use a dripper.
You don't need to see him drink because chances are you won't. Just keep an eye on his poop if the urates aren't white he needs more water. If you're finding it to be a problem a dripper is a cheap thing to start with if you can't get an automatic mister right away.
I think that might actually be what I read
If you get a single dome light make sure to get it from a hardware store not a pet store they're so much less expensive. But you can just use one side of your double if you have enough space for it.
I understand completely why you purchased them and it's great that you actually had two open cages for their use! We have a PetSmart locally and I cannot go there anymore because of how they keep their chameleon. I have reached out to the store owner who basically said "that's how it is and it...
personal opinion:
Unfortunately when you "rescue" from a pet store it just adds to their numbers so they'll just replace the animal and continue getting more. Not saying you didn't necessarily do the right thing in getting them but I think the reptile community needs to stay away from pet store...
With the lights for the chameleon I don't think you'd need an extra plant light. You should be fine with out. If you're in a dry climate (or dry office as they usually are) you can wrap up to three sides of the enclosure leaving the front and top open.
Also as far as drainage goes you can get a...