Exactly, and smoked brakes can be detected afterward.
Regardless of the usual scenario, in this case it happened on an off-ramp, which generally (but not always) is a relatively short distance. You stated that either the car would slow down OR the brakes would break or show damage. This seems to be removing the possibility that the brakes would merely show additional wear.
Given a short (assumed) distance, I don’t think you can rule out that possibility.
They can if you are looking there. But if your intent is to cover up so you have no liability, then you might have trouble finding the real cause. Do you honestly think these people all just decided to drive very fast and smash into things.? When the same cars have the same problem over and over, you get a clue or two.
I don’t see how the normal mats create a problem - we switched our factory mats out for much thicker ones specifically for winter conditions years ago, and have had no trouble with them when they’re in the proper position.