I think it's pretty difficult to discuss the emails without the actual text of the emails here.
We can't see the headers, and those might tell us something. In other words, did Jaycee always work from the same place, ie., the house, or was she ever working from anyplace else with another computer while others were away? (IE, locked up next door).
I don't know if PG wrote emails for his business, or if Jaycee was the only one, but it would be interesting to know if HE ever sent emails or did work using the Molinos' computers, esp. if he was over there a lot. Headers would be revealing.
I'm not sure how relevant it is to the case, but I'd love to know if Jaycee was "allowed" to search for photos on the internet to use for the business cards, or how that worked.
As for any spelling mistakes or other errors in her emails, Jaycee has nothing to be ashamed of. The more I hear about this young lady, the more impressed I am by her. She is obviously someone who did miracles with the limited education she had, and she has the drive and interest to learn. If her emails weren't exactly business-like or had lower-case "i's" rather than capitals, that is something easily corrected. She simply didn't know any better, and nobody was teaching her but herself. If the small I's can be interpreted psychologically, I leave up to others.
Ironically, the fact that she was communicating with people on an everyday basis on the phone and computer for business is one semi-"healthy" thing about the whole experience. At least she dealt with the public to some extent, and wasn't TOTALLY cloistered, silenced. (Nonetheless, I realize that while, in some ways, she was the "face" of the business, her real identity and so much about her, was indeed buried.)