Looks like he couldn't find the parking brake/park button or thought that the car was already in park. Panic when it started moving, and the pressed the wrong pedal.
2020 footage..... old hat. He apparantly stopped, hill hold engaged then reached back fo his briefcase on the back seat whilst pressing down on the....
It has been shared on here previously many years ago.
The explanation from the owner is also well documented.
The anti EV brigade were not slow in saying the car did it itself at the time.... and it was therefore widely circulated on social media with that false narrative.