Ford India — Fire accident

I have Ford Ecosports diesel. On 7th December 2021 my vehicle got fired while I was driving in chennai. Fire caught half of bonnet and the flames were at 3 ft height. We all saved by God's grace.
After 20days of close follow-up with Ford, they responded to me that this Fire accident is because of non standard head lamp relay. Actually I haven't touched any of their HL wiring. I only replaced HL bulb ( I am not sure which brand it replaced, but it is definitely either Philips or Osram which already OE brand). I haven't disturbed any of the OE wiring. Moreover this change was 3+yrs before.

My suspect is that battery got overcharged by Alternator. There is a malfunction between Alternator, battery & ECU.

But Ford is refusing to take this. They are simply rejecting my claim and closing the complaint.