Bowser needs a veterinarian; that is plain and simple. It's not a small problem; it's a chronic condition that has been ongoing for quite a while and even an expert would be challenged by it because frogs recover from maladies slowly.

Still; don't stress out if your parent's decision does not follow our recommendations. It's hard to listen to some frog crazies in a forum when the local expert boy at PETCO or others tells them otherwise. Also, doing a little bit of this advice and a little bit of that one, usually leads to bad results, with frogs and in life. Recommend try not to worry about normal behavior like shedding and most important, pass that worry to parents.

Maybe it's time to take a step back and if not going to veterinary; continue to offer (not force) frog nutritious food (night crawler body length pieces dusted with Repta Boost or CA/D3) and hope for the best. Good luck !