Problem with this is people with blinking blue light out of the box have the issue that the controller is not synced to the PS4 and cant sync with it while the PS4 is blinking. I just tried this and my controller just flashes white every now and then as its trying to sync but it cant. and without it synced I cant do that process. I wonder if there is a keyboard button press one could do that = the PS button or something that works via usb.
Edit: My USB port is unpowered with my PS4 on so I don't think a keyboard or anything USB will work but I could be wrong.
But good find I hope this is all the issue really is!