Hello! Welcome to the community. Your Cham is such a cutie! I love his little spots on his side.
One thing that helped me raise the humidity of the screen cage is to attach a plastic board to the back, on the outside of the cage. I also painted it so it looks like the jungle. I’ll attach a picture so you can see I forget the type of plastic but it came in a roll on Amazon. I just punched holes in the sides and zip-tied it to the corners of the cage. As a bonus it also protects the wall from getting sprayed by the mister. So far I’ve only covered one side of the cage, but it’s gotten way dryer in my area over winter so I might try doing the sides too until spring. Adding more live plants will also help raise the humidity, or as your live plants you already have grow that will help too.
Additionally, you will need a multivitamin. There are many available. Here is a resource that describes the benefits of some main brands. I use ZooMed Reptivite without D3. Make sure the multivitamin you get doesn’t have d3, since you’re already dosing a calcium WITH d3 every other week. I’ve made that mistake before.
https://chameleonacademy.com/ep-125-chameleon-supplementation-basics/
Also, could you measure the distance from the UV light to his basking spot? It could be too close or far away, but since you’re giving him the Calcium with D it might not be a huge issue.
When you measure the temperature when he basks, could you see how hot his cask gets? That’s the part that usually gets burned since it’s much closer to the heat than the rest of his actual body.
One more thing, if possible, could you snap a picture of his full face? I can kind of see a dark spot on the front of his right lip area in the last picture, but I’m not sure if that’s just a shadow.