Hey, I am sorry that your buddy is not doing well. I see alot of people have chimed in with good advice, I agree you should
Replace the lights if you haven't yet, 10 months seems a bit long, I've always heard you need to get new bulbs at 6 months. I recently had to replace a uvb after just 4 months.
I think I read you live up north in MA, I'm not sure what the weather is there as of now, but if the sun is out and temps are above 75 I would let your baby out to get some real sunshine rays, even if only for 30 minutes.
I use repashy calcium plus too, and it is suppose to work like a multivitamin. Some people say they use it everyday, others say it's best to use it once a week, it does have d3 in it though, so if you are suspecting a overly high amount of d3, I would switch to a just calcium supplement (like zoo med repti calcium without d3, I ordered mine from Amazon for 7$. Its a big ass jar too.)
You stated you gut load with bug burgers, and also dust feeders with repashy calcium plus daily, so If it is a nutrient thing causing it, I'd say it's from TOO much, rather then not enough.
Maybe you could go a week without any supplements (as long as the vet said all the nutrient levels are stable, did you get a blood work done?) Or just use calcium without d3 only (not the repashy cal. Plus) and get your baby into the sun some, that way he will create his own d3 naturally and cannot overdose. Sometimes ones own body is the best remedy!!
Personally, I 100% stand behind the "being babied" theory. You know that horrifying saying from 40 year old virgin?? "IF YOU DONT USE IT, YOU LOOSE IT!!" While not being true for Male reproduction organs, it is very true for many, many other situations. Chameleon tongues being one. It could simply just be that he hasn't had to release his strongest muscle in full force for an extended period of time, so his tongue is just a bit rusty now. Keep putting feeders in that he has to hunt, and he will slowly regain his ability, and confidence!!
Okay, this is the key point to why I'm chiming in, and I wish I could say it wasn't sad, but the reality is 4 years is getting up there in terms of chameleon life span. Specifically ambilobe Panthers have a life span of 5- 7 years in top notch environments. Yes some go beyond 7 years, but a higher percentage falls on the lower end of the scale. I'm also under the impression your baby has been sick before, at least once with coccidia, but I vaguely recall reading he got sick more then once. Any illness takes a toll on a living creature, any and all living creatures. I have a bulldog that has been through alot in his life, got attacked by a dog and needed stitches, got shot in the head with a 38 hollow point by neighbor, consequently got lockjaw and had to have another surgery to remove his left mandible so his mouth could open, got in another dog fight when introduced to my brothers Male Irish setter, point being - every time hes got wounded, the vet verbally informed me everytime of the impact it has on life span. He is still very much a happy loving active dog (just has a unique face now [: ) but the stress causes excessive wear and tear on the body and soul.
It's kind of like, imagine that when we are born, we have a little life bar (like seen on videogames) This life bar is filled all the way up with energy, this is ALL the energy you get in your life time. from the moment you take your first breathe to every step you take, every blink, sneeze, every peanut m&m you chew, you are constantly loosing energy from your life bar at a slow steady rate. But say you fall and scrape your knee, a tiny bit more of your energy disappears. And then a year later you break your arm!! There goes another slither, a but more then when you scraped your knee, but far less then if you say get open heart surgery. You constantly loose energy at a steady rate, plus all the bursts of energy sucked from you each time you get sick or injured. If you suffer from any underlying long term illness, your daily rate of energy loss is doubled, maybe tripled. So as you can imagine, someone who has been in various accidents, had surgery after surgery, had the chicken pox, the flu, food poisoning - their life bar will run out faster then the person who fell off their bike as a kid and never rode again. The catch is every living thing has a unique life bar, and nobody knows how much energy they have to begin with!!
It sounds and looks like you have given him a wonderful life full of love and meals and I hope yall still have more years to go, but In case the time for eternal peace is near, I felt you shouldnt be blindsided. Keep your head up, and keep helping him the way you feel best, trust your gut.
Best wishes for you both, Jessy