Reading through the introductory Erika reboot video, and responses:
A) Gloriously hilarious. "A regular Ushiromiya family reunion" in particular is hilarious.
B) Poor Sakutarou. He must be so sad that Maria rejected him. Oh wait, no he won't, because he's extra-perma-dead now. You monster!
C) Watching Erika horribly embarrass herself like fifty times before she realized that
yes, these are actually the Ushiromiya survivors is hilarious.
D) Totally-not-Ikuko/Featherine is a
terrible mother. (And I wonder who the father is? Timeline's all wrong for it to be Battler/Touya...
E) "Progeny: Are you well?" Also, searching Hachijou's desk before opening her own luggage. Man, Erika is a
terrible roommate (very surprising, I'm sure.)
F) "My parents must have been very upset with me in this Fragment. Can't imagine why."
And moving on to "the next morning" - it strikes me that Maria is actually one of the very few people who could come to the correct conclusion (Erika is a Witch from the past who witnessed scenes from Rokkenjima.) Of course, that would require her to start believing in Beatrice again, but hey! It could happen!
... it's more likely from her than anyone else in the story, anyway :P.