Long-shot, looked at the pics. What do the wires going into the headlight connector look like? When mine melted, it wasn't immediately obvious from the outside. Maybe stuff got hot at that interface and the fire spread down the insulation on the wiring?
IDK tho, just sayin' my headlight connectors were melted to f* when I took them out thinking I was about to replace some bulbs. Had to replace them both, and used ceramic.