I know of instances when a car went into the overhead and crashed, the car got stuck in the overhead, car safties applied.
This must be somthing that you are really trying to get the answer you want and won't let it go. That car would not have recovered in that instance, and yes there would be new skivies involved. Use your BS detector. The car would not have lowered if the case was that it slipped traction in the up direction. If it was overspeeding in the up direction most likley it would have tripped the overspeed switch on the governor, top final, both of which is in the safety circuit. 21 is not a highrise.