Hey Kisa, is he/she still having trouble shedding?

The raised humidity should help and something has to be drying the skin out just enough to not let it peel off. I the frog is spending much time on the paper towels, the paper towels could be pulling mositure away from the frog.

If your paper towels are kept damp, it may help with reducing the chance of the above issue (if thats what happening).

Not sure what else might help you and hopefully the condition corrects itself so Bruce sheds normal again.