Chance of fire, certainly, before the vehicle came to a stop. In this chance, it would appear that the driver had maintained control despite the fire.
Vehicle appears to have exploded after it came to a stop.
A vehicle that exlodes while underway on a highway, loses control - unless somehow the driver remains in control.
Yet, there can be a “freak occurence” in that, despite a driver being unconcious or deceased, the vehicle comes to a stop. This is rare.
Adding: Look at the vehicle. It is aligned within the high speed aka passing lane, having the appearance of a controlled stop.
I suppose that a late model vehicle with so many computer sensors and controls, could detect fire and extreme heat, and bring itself under control - including alignment within the lane of its travel.