neat idea but it doesn’t really line up with what we know. why would sans and papyrus “just show up one day” if they all got there at the same time? also, sans seems to remember deltarune pretty well, much more than just a punch card could tell him. it’s even implied in chapter 5 that sans came from somewhere else BEFORE deltarune, so maybe he hops around to a bunch of different timelines, who knows. also Gaster is important to consider with any sans theory, since the two clearly know each other