Poor guy sounds like he’s been thru a lot. Chameleons are very sensitive to changes and get stressed easily. However, you need to make the changes to improve his life. I think the plants will definitely make him feel more secure and settle in a bit better.
Is there any way for you to get the glass top removed and replace it with screen? Having a glass top is going to make it very difficult to give him the correct lighting. Hybrid and glass enclosures are fine, but you need to ensure it has good air circulation and a screen top. A good glass enclosure will have some ventilation, usually on the lower front of the enclosure and then the air is drawn in and up thru the screen top. Like in this glass enclosure, you can see the black vent just below the doors. *only using this pic to demonstrate…this is not a good enclosure example for a chameleon.
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