"Aisha, you don't need to have anything to do with those colors if you don't want to." I assured her.
"I know, but it's an opportunity, right?" She asked. "You couldn't figure them out, and then my power works with Ren and suddenly there's a way to use them, right?"
I like how you've found another way for Aisha to "contribute" to the Celestial Forge's crafting projects, with the Lethe water and celestial bronze, and now a means to directly manipulate the un-color from the Prismatic Laboratory.
Aisha wants to be a team player and feel worthy of her friends' faith, so her memory-based Stranger powers being the key to Garment's un-color R&D is a great plot twist and a natural extension of Aisha's character growth.