Totally feel for you @Macs ! That is a definite bummer. I had a truck stolen and after the fact, it wasn't the truck that I missed. It was all the small, personal crap I kept in the thing. Sorry for the loss and anything personal that was inside it.

This burn was even worse that my college girlfriend's. She would always toss her keys on the dash and say, if someone wants to steal it - they can have it! One day someone stole it, stripped it, and then burned it. I took her to see the pile of burnt ash that looked almost as bad as that. She was crying and I was laughing. Yeah, we didn't last long.

I agree @WTFChuck . ANYTHING could be at fault here. However, your later thread where you say the "Add oil light" came on gives me a suspicion of an oil leak. 30 years as an EMT, I've seen a lot of car fires. Even had one myself. When going at speed, people rarely notice the smoke until they either stop or it is REALLY bad. So, I'm still thinking "oil leak" could be a factor. What caused that leak? Who knows. However, the Defenders have a "crap ton" of telematics going on. You don't have to pull the codes from the OBD any more. Most vehicle history & fault codes are pulled remotely from cloud storage. Not sure if it's JLR's process, but MANY manufacturers do and I'd be surprised if they don't. If you have the Remote app (or have access to it), I'd recommend trying to log in and see if that gives you more info.

Good luck and as others have stated: hope you have insurance and/or an attorney.