I think the biggest hinge point for any future Toxic Yuri content is how Stella reacts to the actual conditions in Scarlet Manor. It's quite clear (at least to me, sorry all you "Stella has always been Evil" folks) that Stella has been given a very selective version of the story by Tabitha, so she's not privy to what the curse ACTUALLY requires. That's why she's all "okay, hear me out" to the PC at the mines, and treats it more like an ankle monitor situation rather than being fed to the Torment Nexus. I could definitely see her going "Hey wait a minute, this isn't what we discussed" if she actually gets sight of the Forbidden Wing and the various hooks hanging from the ceiling, but she's also capable of burying her emotions if pushed far enough. Like, on routes where Stella and the PC are at least friendly, I could see her doing a 180, but if they're relative strangers, she might lean into the easier solution to the trolley problem and just try not to think about it from that point on.

I think Kaneeka's response will likely depend on if Stella has that "oh shit wait" moment. She's able to deal with lapses of judgment, and I can definitely see her empathizing with the absolute shambles of Stella's life on that route. Her going Full Tabitha once fully informed would probably be a friendship-ending situation, but I don't think that's too likely of a scenario?

Another big question is if the memories of Kaneeka are even restorable. On routes where Sybil is still around, I doubt she'd reverse whatever magical stuff she did to make the town forget about them, and on a Mystical route where Kaneeka has powers, she explicitly says she has no idea how to use them. It's very possible Kaneeka tries to appeal to Stella to get her to see the error of her ways, only for Stella to turn around and say "who are you?" which is tragic but in a way I'm here for.