I’m not sure if I’d feed meal worms, they are pretty high in protein. Some things that I use as treats for my conures are seeds, little bits of chopped nuts, bits of chopped fruit, bit of millet, pine nuts, safflower seeds (all in moderation of course) .
Almond slivers, diced carrot, peas (fresh or dried), and dried papaya bits are my Yoda's favorite treat rewards. I wouldn't recommend meal worms personally.