Going with your thought CE =)
Does anyone remember hearing a couple people (female voices is what I recall) talking about him being a "good" father, they'd talk about parenting advice and such (the female and Czarina, not Maria and Czarina)
Well, I'm sure if there is any remote truth to those statements, Then Maria would have witnessed it firsthand, that had to be a huge bonus, on top of the fact that guy was charming, cute, social circle, and IIRC someone mentioned (not sure if's it's true but...it does sort of fit) that Xtina and Czarina had broken up/seperated/were fighting/ during the time the rape allegations were made (I want to say it was an Lejuene Underground??)
My point being, is he could have been feeding her every line in the book. ESP. If wifey was "out of the home" for a bit. Or he was...That would explain the pin number being known too possibly....
Not stating, it happened that way, etc etc etc. Just adding on to CE's post, because those were two things that popped into my head when attempting to place my thoughts to the above scenario.