Comments of chapter undefined of Human Sans

Well, now it's obvious that these events happened after a slightly modified true pacifist ending, considering the fact that actual Asriel is here and not in the form of a humanized Flowey. What happened to the other humans? No, not just Chara, I mean all of them. I mean their corpses were underground and after a true pacifist ending they seemingly leave the coffins. So, are they going to make an appearance or are they just nonexistant here?