At this age you don't really need to try fruits or veggies. At 8 months or less veileds don't need much plant fibers in their diet at all. You need to focus on feeding insects and getting it right first. What you need to focus on is gutloading the insects. So feed the insects healthy fruits and veggies, like specifically dino/tuscan kale, mustard greens, dandelion greens, figs, papaya, mangoes, collard greens on occasion, arugala, turnip greens, water cress, parsley, some basil occasionally, chicory leaves, chard (not swiss chard), beet greens. I often use all my feeders like roaches/crickets as green waste disposals most of the time.
Edit: I would look into a large cage soon. It will be easier to stop him from getting burnt in a larger cage with a better range for temp gradient. You also want the bottom of the cage to be as bare as possible, so the most you want is paper towels. If you are sticking with fake plants, be careful because your chameleon is a veiled and will eat their enclosure plants, even if they are fake. Live and chameleon safe plants are best. You still need a lot more plants. Hopefully he will be hard to find by the end. You also want several more branches with different kinds of textures.