Mold in a FF culture is generally not a good thing, particularly from the perspective of culture productivity. I have seen a few cultures literally crash in the presence of mold.
While I doubt that it would hurt your frogs, keeping those cultures is just going to lead to the production of a large number of mold spores and may lead to you dealing with even larger levels of contamination in your cultures in the future. My advice would be to pitch them. FWIW.