Chosen Solution
Hi, I would try cleaning up the underside of the pcb with Isopropyl Alcohol 90%+ to ascertain the damage. It may not be as bad as you think. If the tracks are still OK and not burnt through so that there still is a connection from the “connector through hole” point then whilst the connector may have to be replaced, the board still may work. If difficult to source the correct connector part (mouser.com) you may be able to remove the connector and pass the wires (remove the ends and clean up the wires, (ensure that the wire insulation is flush with the topside of the pcb -no exposed wire on the topside) through the holes and terminate (solder) them directly onto the board. If it works after doing a “modified” repair, cover the soldered wire connections on the pcb with a neutral cure silicon sealer to insulate the connection and make it just a bit safer for somebody else down the track who may work on it ;-) Once arcing occurs you create resistance which affects the current flow and generates heat until it is burnt out and then there is no current flow
