Does Erisolsprite currently exist in any form? Is Sollux alive, half dead, or entirely dead? Does the current Sollux have any memories from the time part of himself was Erisol?

Erisolsprite may exist if he hitched a ride on Lowas like Davesprite and Nannasprite

The current, post retcon, Sollux is half-dead. This Sollux was never apart of Erisolsprite and therefore has no memory of it.