If it not peeling, then it is probably a burn, as the skin looks like it is about to fall off. How close is he to his heat and UVB lamps?The humidity is good, but you definitely want to get some live plants. Live plants are one of the most important parts. They provide humidity, more roaming space, and the chameleons can munch on them.
You also need to mist him at least 4 times a day. I would suggest misting him every hour though, like with a MistKing or Monsoon which you can buy at most pet stores. Now that he is older, you may want to ease up on the food. At 8 months, I was feeding my female every other day. Granted yours is male, but you do not want him to get overweight.
It looks like his eyes are sunken. He may not be drinking as much as you though. I am pretty sure if you start misting more, or dripping, he will be able to drink more. The problem is he doesn't get enough water just once a day. They drink through the day. This may be your problem.
Carrots for the crickets is a bit redundant. Carrots have beta carotene, which chameleons can't digest. You may want to switch to something like collard greens and definitely more vegetables.
Here is a link for gutloading ingredients:
https://www.chameleonforums.com/threads/gutloading-ingredients.161898/
Hope this helped!
