HW2 doesn't make sense to me

Carnie and the toys on the carasoul at fall fest existing would seem to put the Rockstars and the toys in the 70s, so why do they disappear until 1987 and 20XX (whenever FFPS is) respectively? Additionally if this is supposed to be the Vanni mask distorting reality, how are we seeing SL or Fall fest if they happened in the past and fall fest can't be in Fazburger because MCM already existed (iirc) and given the design of the scooper in ruin, the mimic being in the pizza plex, and the Mimic's costumes being in the pizza plex, MCM is definitely in the Fazburger, maybe there was another fall fest sometime after ffps, around the time of the Pizza plex? Or maybe spookfest referenced in a poster in ffps? Idk I just find it kinda confusing, might just be missing something though, sorry for any mistakes or grammar issues, writing this at 3 am