What happens to other Auras on a Creature enchanted with bestowing, when the Creature dies?
Aqueous Form goes to the graveyard.

It doesn't attach to the newly-a-creature Thassa's Emissary, because it wasn't enchanting Thassa's Emissary - it was enchanting the Cyclops, which has left the battlefield.

Bestow comes with exceptions that let Thassa's Emissary simply become an Enchantment Creature once it's no longer attached, but there's nothing saying that it brings with it its formerly bestowed creature's auras.