For everyone calling her "omnipresent", she only says "I know everything". I know it's barely a difference, but the latter can definitely be used as an exaggeration and to hand wave her knowing something they wouldn't expect her to know. As for whether that was the intention, or she really means she knows everything, I don't know. She did know where the angel twins were, but it's also Panty & Stocking, so they don't really have to explain shit if they don't want to.