Besond seat heater failure ideas

So about 5 months ago, when i did my leather, i ordered seat heaters. I figured since the seat was already going to be apart, may as well have them lay the elements.
I ran the wiring. (which i will never do again, that was royal pain) Did everything clean.

Seat heater stopped working last night, but the switch was still illuminated, and I couldnt hear the relay click, so i thought it was the main fuse at the battery. nope, that was good.

Pull the HU this morning to get to the wiring to start tracing it back, and discovered the actual plug to the switch controller burned up, yet didnt pop a fuse.
The company is sending me a new harness, which is cool of them.

anyone have any issues with rostras or any other aftermarket seat heaters? Im alittle sketched out at this point, not sure im going to keep using them once i get the harness.
Ill add a photo shortly.

 

anything i should test or go over?