I think its important to make sure your soil is very welp draining. Most house plants arent acclimated to enclosure conditions, and aren’t used to all the moisture. If it is yellowing your options are to cut back watering (cant do that in this case), or increase drainage.
A good chunky soil mix will allow air to circulate around the plant roots, and will allow excess water to flush out. I would charcoal and/or orchid bark to the soil - a lot of it. You can then spread a 2” layer of plain soil on top if there is concern of your chameleon eating the chunks.
Typically in tropical house plants I try to mix equal parts peat, perlite (omit in cham cages), charcoal, and orchid bark. Sometimes I add other stuff, too. The exception being bog plants and plants that like “wet feet” like hibiscus.
Chunking up your soil will help - its not going to reverse the damage but should help going forward. Make sure the roots aren’t rotten (mushy black) when you repot.
