I just don't know what to do

I've had Dovah since November. He was born sometime in September of 2018, so he's an adult now. He is an extremely picky eater, and he hates a LOT of things.
He doesn't like bee pollen granules (can't find the powder, but that might be my next experiment), doesn't like mustard greens, doesn't like anything colored red or orange. Doesn't like wax worms, doesn't like BSFL (gut loaded and unloaded). Has an extra disinterest in Dubia roaches (I've tried several times, with several different gut loaders, with several different sizes). What DOES he like? Hornworms and blueberries. That's all I can reliably get him to eat. Now, obviously, that's a major issue! I can often get him to eat several bites of zucchini, peeled cucumber, yellow squash, kale, and turnip greens. I think he's beginning to like snap peas and sweet potato. But the main issue, is he just won't eat his bugs!
I took him to a very highly rated vet, and he was prescribed some medicine for a mild pinworm (maybe? Can't remember) case. She said he was skinny- but not in an unhealthy way. I can't get him to drink, either.
I'm trying the Rapshey's Grub Pie and Beardie Buffet (they're cooling down now). He acts like a normal beardie besides all that! Loves cuddles, likes to watch cars go by, and he's even getting used to going outside and being on his little leash.
His basking spot ranges from 98-95, below that can be 90-85 (depending on where he sits) and his cool side can go down to 75-80. I have a CHE keeping his cool side at 75~ nightly, at the request of my vet. He has finished his medicine. He's a very loving boy, and im just so scared I'm doing something wrong. I see people's bearded dragons go crazy over insects, but Dovah won't! His vet told me to try the new hotter nighttime temps (before it would go down to 70-68, as I live in an old house).
I just dont know what to do. I'm terrified that I'm doing it all wrong! Dovah is my first lizard, and my second reptile. I just need help!
(UVB- Reptisun T5HO)
(Basking bulb- Reptiglo)
I get my produce from Walmart if that matters. Usually got the feeders from Josh's frogs, or rainbow mealworms)

I dont know if this makes any difference but that Reptiglo is it a bright white basking bulb? I know Reptiglo UVB's are bad so I just had to ask ---- have you tried silk worms? They are a great staple feeder ---produce from Walmart is fine--- if you would like to try some silk worms I can give you some websites -- he needs a protein what about crickets? Horn worms are good for hydration and blueberries have too much sugar --- have your tried super worms butter worms meal worms?
Karrie

I will try silkworms! And yes, the reptiglo is a bright white bulb. As for crickets, my parents don't want me to keep them (I'm staying with them until I finish my college degree, probably). I might be able to convince them otherwise. I did try butterworms, again, no interest. I will get some meal worms to try as well! Thank you so much for such a quick reply!!

Update: his rashes gels just cooled so I gave him some! Good news- he LOVES one of them!!! Bad news is, I didn't label which one is which, so I have some more guesswork ahead of me?

Update 2: he is eating the other one, but has an obvious preference. I think he likes the beardie buffet more