WHOA! That's a new theory, but it could be possible, though I think it's unlikely. I don't have a strong reason as to why. My doubts stem from her really poor spelling and writing skills. How was she able to do any research with such poor spelling, how would she look up any names.
The little that we know about her, she doesn't strike me as a bright woman who could continuously carry out identity thefts.
I wouldn't doubt that her in-laws found her genealogy searches hypocritical, ironic and strange. I wouldn't have given her any information. What did she do with all the results from her research on the family?
I'm wondering if FLEK actually had any known blood relatives? Was she adopted, adopted and abused; a foster child who didn't know anything about her biological background? I keep wondering about this.