This mistress wanted to find out why this slave had disobeyed her and she was opened minded about it. But the guy pissed her off further by not telling her what she wanted to know. And that is why she chose top punish him by trampling him. She used trampling mania to do it and she did not need to even do it for long for it to have an impact.
This guy was in need of some degradation according to mistress Lisa and princess Kimberly. He had angered them and they retaliated by trampling him with their sneakers. He could not believe it and he tried to dissuade them from doing it but they did not care and they had to finish what they had already started. He realized he had fucked up and he apologized before they let him go.