I also posted every choice I made in the nighttime portions specifically because I don't know which ones do or don't affect the final result. What I assume is that, for Chiku, you have to do the whole scene where you talk to all of them in Night 2 to get a better idea of who they used to be, for Night 4 do the "Vacuum Booths" task first to get to talk to her and discover the kitchen, and then for Night 5 leave "Prepare Dough" for last since Chiku doesn't show up before then.
As for Lexy, I'm gonna guess you either bought the counter-ward later than Night 7, in which case the solution is simple, or made a different choice at one point that had a domino effect on something else, in which case I don't know what you could have done differently since I don't know what you did in the first place.
