Oof I don't like bad endings either since I'm one of those people that lowkey actually care for the characters and I don't want them to suffer 😅🙈 so i wish you good luck to writing the remaining bad endings
Also I agree with both the previous comments. I think if you think that recruiting a new proofreader would be beneficial then go for it. Definitely think this could be something to ask the remaining proofreader how they feel and maybe they'll know someone who would be interested in becoming a proofreader.
I hope everything works out and I hope this week for you goes well too!