I wonder where Amon/Hermes was taken when Asahi dragged him into a dark portal? Felt like a loose end since even when Metion at the end of Endwalker also wonders if Hermes will ever find the answers?

I seldom consider there ever being a 7 Hells as literal place (with it being mentioned in passing in Pandemonium Anabaseious 12) in the story, but the possibility of him being dragged to a place elsewhere in the Atherial sea is not out of the realm of possibilities.