I also think that the date issue is a big red flag. According to the documents, the picture was downloaded on the computer the same day the picture was taken.
You find out your granddaughter is gone, you can't remember the date she went missing, but you would remember the day, Father's Day. You would find a calendar, go on the computer and look for the last picture taken......for 2 reasons, one to figure out the exact date and one to give to LE for identity purposes.
Remember, Cindy said at the bond hearing, she never realized it was June 15th til the night before when LE told her. They got it from the A's computer. The same computer (I am assuming)that she and Casey were on the 16th making a myspace page and contacting everyone.
In my mind, that is one of the most important pieces of imformation that you would give LE concerning your "missing" granddaughter.