What in Tarnation - No power to Head Unit

Aftermarket unit, with backup cam, was on the fritz during my drive home yesterday.
Got home and found the backup wire was shredded due to the tailgate action.

Fixed that. Replaced the fuses: 30A, 10A in engine bay, 10A in headunit. Unit, a Kenwood, gets the 'pilot' light on and that is it.
The wires were bungled coming into the cab on the drivers side, so those got fixed as well.
Two connectors were unplugged upon inspecting behind the footwell panel. This 5-prong
And a 10-prong? with a purple wire labeled Reverse. It has a clamp style lug, and for some reason, 2 wires, one cut end, in the crimp. I plugged it in, though I am questioning whether it should stay that way or not. Still no power. There is also a body-ground that was cut, which you can see the lug of in the second picture bottom left.

Any help would be much appreciated.

 

at the head unit connector, with the truck accessory turned on, take your volt meter and check the following:

black to red: should be 12v.
black to yellow: should be 12v.

put the truck in reverse(just need to turn the truck on, don't need to start it), and check the black to reverse wire-- should also be 12v.


if all that checks out, all those shredded wires likely cooked the head unit from the inside, and it's time for a replacement.