Given that there wasn't a war on in the area at the time of the crash and given that it is not the USN that has the ability to shut down, or actually, re-apply the fudge factor, but the Pentagon, then I think it is highly unlikely that nefarious GPS signals had anything to do with catastrophe.
Furthermore, the military use a different signal to the civilian one so they had no need to mess with it at all.
Some people on this forum should really learn and apply Occam's Razor. It really helps in lowering the paranoia levels.
