NEED HELP - Moto X 2014 Everything black?

Moto X 2014: unrooted with bootloader unlocked. It's running Stock 5.1 and I haven't messed with anything on it. I gave it to my Dad after a few months of using it, so I factory reset it and gave it to him, 2 weeks later he tells me it has stopped working. It boots up normally, but from then on it is black, I can access minor parts of the OS such as the power off menu, the camera (by shaking) and Moto Display, but everything else doesn't work. I have never seen anything like this before, and I am well accustomed to flashing custom ROMs and rooting Android. If it comes down to it I will factory reset it or flash stock, but I can't even plug it into my PC and retrieve any files. Anyone have any idea whats gone wrong?

I have attached a video demonstrating what's happened to help diagnose the problem.