Im in the same situation with my dragon, he stopped eating greens at about 6-8 months old.
Ive tried holding out on protein and he just won't go for it. Ive tried Kale,Dandelion,Turnip,Collard,Mustard. He used to eat Turnip,Collard,Mustard Greens as a staple every day salad and he loved them, Occasionally I would add in some butternut squash and he would eat that as well. Ive put various worms in and he might get a bite or two but thats it, he won't go for it. He had some Pin-Worms that we treated for and he is acting better and will eat his protein much easier, but still no greens?