Comment: It could have slingshotted

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It could have slingshotted

It could have slingshotted backwards if the last remaining link was the driveshaft. A car hitting a tree does bounce back a little. This combined with the 5000RPM of stored energy it could have rolled backwards. This assumes that the engine mounts and transmission mounts took the brunt of the deceleration prior to being peeled away from the drivetrain as the tree disintegrated the the car.
Others and a scientist on this forum disagree but this is the only plausible explanation I can think of. An explosion powerful enough to rip an engine from a car 200 ft surely would have left much more evidence.