Just keep offering those veggies. One of these days he will surprise you! Have you tried different versions? I.e. raw, steamed, mashed. Sometimes they won't eat a veggie raw but will try it off a spoon if it is steamed or mashed. As you may have guessed, Timber is spoiled. However, I don't spend ALL day standing there with a spoon... Also, try a skewer hanging in the cage. Timber started out just attacking the veggies and pulling them off but has progressed to nibbling a little along the way.