804
(dnd 5e) Prove me wrong, RAW
(sh.itjust.works)
Disclaimer: this is purposefully obtuse.
Other effects in the game which explicitly state they kill you:
Shadows, succubi, massive damage, death saving throws, beholder death ray (notably not even their disintegration ray kills you), power word kill, vampires, mind flayers, night hags, drow inquisitors.
Clearly, if they intended for disintegration to kill you, they'd have said so. Since specific overrides general, and there is no general rule that disintegrated creatures are dead, I rest my case. QED.
I was thinking they might learn or get enchanted with a minor wind cantrip that they can cast on themselves infinite times, and rearrange themselves into words.
They can communicate with any literate character, but slowly, only in words that are short enough. Otherwise they have fo finish the word on their next turn.
If it's genuinely windy in game, the player has to write their communication with their off hand, blindfold whilst someome shakes them or the paper randomly.