Took Bufo to reptile vet and found the tongue problem was probably due to a calcium defiency.

He gave me calcium drops to administer to Bufo orally and suggested I switch her food from meal-worms to crickets gut loaded with calcium feed. He also said to use a UV light on Bufo 4 hours per day because it breaks down vitamins and helps toads absorb calcium.

So, I try that.