Well, I believe it is the fuse box that burnt and spread the
fire, the surge of current out of a sudden could had burnt the
fuse, too late for it to cut off, just like a high surge of current
into a bulb, it blown off before even the tungsten broke.
If your vehicle had a sudden bright front lights, then dim now,
then suddenly bright again, such inconsistency happen in korea make
car, cos their circuit and board technology in auto industrial is
still no as good as the Jap and German.
On the other hand, due to fuse keep blowing up out
of inconsistency of current surge, those farking mechanic may
put an above the safety Ampere fuse to stop the blowing up,
this heat up the fuse till red hot and burnt.