I watched most of the first video.
I think this guy is sick and he admitted he has been seeing psychiatrist.

The story told is incomplete.
He started the story with him coming back from holiday and just rescinded his resignation.
Why did he go for holiday? Why tender resign? Why pull back the resignation?
These are important fact to determine whether what happened next is logical or fair.
Without these fact we are unable to know for sure if the company is wrong.

Regardless to above, if what he stated about the company executives' conducts are accurate or near to the reality,
the company handled the issue badly.
However, we need to listen from the company side as well.
So we have no conclusion about this by just watching the video, except that we are certain that the company's chosen course of action has lead to a lose-lose outcome for all parties involved.

This guy is sick and he cannot think properly.
First, the company tried to offer help after initial mismanaging. He see these actions as 'harassment'.
Secondly, even if we accept his narrative of the events and the company's actions at face value, it is still vey far to establish a case for 'mental abuse'.
So, I dont trust the word he used and his evaluation.

Get well soon.