I always get a little jealous of you foreigners with your dilepses. Flap-necks are one of the species that are indigenous to South Africa, and I'd love to be able to work with our local chams.
Unfortunately, like all indigenous reptiles here, they are protected by law, and we can't keep them.
You can obtain 'catch-and-release' permits, which I believe is what some snake breeders are using to get additional gene material into their breeding pools, and you can get permits to keep animals that were captive-bred, but there is no such thing as a 'catch-and-keep' permit, and it is certainly illegal to catch and sell them.
So, ironically, the only way I could get to keep a flap-neck is by importing it from one of the suppliers in Kenya/Uganda/Tanzania, which is the same source that I presume most people in the US or Europe get theirs from.
I do consider it a privilege though that if I go for a walk in the bush not far from where I live, I can get to see these creatures in the wild.
But I digress... yours looks like a good speciment, but he also looks quite well-grown already. You'll be wanting to get that bigger cage finished as soon as possible, and try to get plenty of foliage (especially live plants) into the cage to give him more privacy.
And that substrate is unnecessary. It just gives the crickets somewhere to hide...
How are you watering him, and what are you doing for drainage at the moment?
the crickets dont free roam i have a shot glass mounted on the side so they dont crawl out the basking temp is around 87 degress where that light is its just a regular reptisun 10.0 bulb so it dosnt get too hot