Hi Spiderlover, as also an owner of WC Cornuta, I have three suggestions. One is that the American bullfrogs have a high chance of carrying chytrid fungus, let it be wild caught, farm-raised, from North America, or Asia. It is something to be cautious about. Two is that Cornutas are notorious for unwilling to feed in captivities. So that leads to my last suggestion: maybe you should think about force-feeding your frog, unless you can condition and train them to eat safer food like crickets, nightcrawlers, or samurai pacman food, etc.
You can keep feeding bullfrogs to them but I'm afraid they'll catch chytridiomycosis sooner or later. Or you can train them to eat the safer food I mentioned previously, but it may not work. So that pretty much leaves you force-feeding these picky frogs, or simply don't purchase WC frogs. There are CB Cornuta babies available that are willing to take safe, healthy food.