After asking this question for clarifications on how the acid damage dealt by the toad's Swallow works, I realised I need another explanation about this attack. A Giant Toad can make a Swallow attack on a creature it has grappled, as follows:
Swallow. The toad makes a bite attack against a Medium or smaller target it is grappling. If the attack hits, the target is swallowed, and the grapple ends. The swallowed target is blinded and restrained [...]
Specifying what happens if said attack hits, the text doesn't mention damage at all. Does this mean Bite is referenced only for its range and attack roll bonus? If yes, then Swallow doesn't deal damage at all, aside from the acid damage starting from the next turn (according to the conclusions drawn from my previous question). If no, then the damage of Bite is rolled and applied, followed by the effects of Swallow. Is this correct?