That kid Adam has a lot of characteristics of someone who was abused. The fact that he never talked to anyone and the mother was ok with that should raise some questions. I'm also not buying that the Feds cant get anything off his computer. Unless the thing was melted in a fire, they would be able to gather info off it.
The kid knew what he was doing, I'm into computers, and their is software out their were you can completely wipe out the contents of hard drive, it needs to be constantly re-written, normal formatting wont do it , but it is very easy to do. You can also use a dirty great big magnet, I used to work for a big auction house, and we used to get all the ex government and police pc's to sell, we had to remove the hard drives and use a power drill to drill straight through the hard drive disk platter. They didn't want to take any chances.