I would just take a couple of leaves that you have on that plant or another one like it and break them off. Then let them dry out and die on the floor.
I think the enclosure looks great. I can not really comment on changes or things to use as I have no experience with those types of chameleons. Again it is very attractive.
The kind I used to use had no long fibers and would not casue impactions if ingested. It is still available, I would not advise using anything with long fibers like that, it is not worth it if it gets stuck in your animal’s digestive tract.