It is their differing needs that are addressed in the attached paper. I would think that on the contrary that there is little to no evidence to suggest that any frogs DON'T need UVB. D3 oral supplementation was invented when people realised that keeping animals indoors away from natural sunlight was causing them harm and figured out that it was the d3 that sunlight was formerly providing that was missing. Back then, the only remedy was to expose the animals to natural sunlight or administer a synthetic. We no longer need the synthetic (which is known to be a poor way to address the problem) as we now have freely available technology to replicate the missing sunlight.
It is not only frogs of course, we know that all animals with very few exceptions process sunlight to produce vitamin d3, and that includes humans. We get the majority of our d3 that way despite a hugely varied diet. As far as larger amphibians are concerned (you'll notice Bufo marinus on the list), while they may be able to meet a certain amount of their requirement IF they find prey that contains it, they wouldn't meet it all that way and almost certainly none at all as juveniles when their diet would be almost entirely insect in nature.