Besides the parking brake, one can turn the ignition off and let the engine decelerate the car, once it slows enough jam it into Park or Reverse. I think if I were headed towards a busy highway with cross traffic, I would spin the steering wheel and hit anything else rather than ram into cross traffic.
All I can say, it is a long way from the Bass parking lot. There are trees and what looks like a small hill from the Bass entrance road to her tree line location. The only normal way to where she was is through a dirt service road on the opposite side of the lake from Bass Pro. Are there skid or drag marks through the mulchy knoll? Makes no sense at all.
My take is someone undid the brakes prior as an excuse if caught.