Responses
Might be cause they can’t figure out the literal date in which he made the wish. Plus it doesn’t really seem like nene has any actual control of where and what time she gets transmigrated into a new timeline/past.
There is also the moral dilemma of stopping Tsukasa's wish (since because of it Amane manage to become healthy) but it's not something that Yashiro or others knew
can't he like stop tsukasa before the kid makes the wish..? I don't if this is a dumb question, forgive me if it is, my exams fried the shit out of my brains