After initially waffling, wife is now insisting that I sent it. She is absolutely sure, beyond a shadow of a doubt. And I have made very little effort to change her mind. I did send a second email to her pointing out a few holes in her logic. And I still don't know the contents of the email, so I can't really say much of anything anyway.
I am done trying. This is a hole that she has dug, and now she is dragging me into it.