I've seen the drivetrain ejected like this in one or two other high force side impacts. Remember that the engine mounts are probably designed to sheer off in a crash, and as BC noted the lock carrier isn't going to provide much resistance to a heavy engine and transmission.

Also, the explosion sound can come from just an impact... doesn't have to be an actual explosion. Even the "slow" crash where my parked Jetta was hit was enough to show me that.

On the fire aspect... it takes minutes for a small fire to fully engulf the car. Look up videos on youtube... the rate at which the fire spreads is amazing. So overall I don't see anything that is a "smoking gun" in this crash, unless some outside influence caused him to lose control in the first place.

-J

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.