[dx034]

The poster said that the brake was fully depressed with around 100kg of force. It won't take long for that to be in a standstill. And there's no way acceleration can overpower that kind of brake power. The sound might be scary but it won't change much about brake performance.

[jacobush]

Bad clutch plus bad brakes (but not so bad as to be unserviceable in light, normal use). Story is not implausible.