[quote=@Sho Minazuki]
They probably already asked her.

She went missing on Friday, and then Ayano would've been approached on Saturday, and now it's Sunday.

Ayano and her family is currently the only one who knows Chiaki is missing.

Except for the dungeon party, but we're still not sure who's in the dungeon, but it's familiar.
[/quote]

But we are definitely experiencing deja vu. We won't know for sure until we see them firsthand.