Most of the worms you keep on hand for your beardie are good for frogs as well. Phoenix worms are a good staple worm. I have heard both good and bad about earthworms. Just be careful with them as to where you get them to ensure they dont have any bad chemicals on them from soil. Also with earth worms you might have to cut them up into segments small enough for the frog as they will not take them if they are to long/big. THey should still move for a little after they are cut up.
I would take the frogs to the vet if you think there might be something wrong. Your gut feeling is usually right and that is the only way to know for sure. Plus if medication is needed that is the only way to know for sure and get the correct med for them.