I think you are correct, this meeting in isolaton is fine. The indirect implications, however, is that this meeting constitutes the full internal review and response to an employee leaving in a disgruntled state. I obviously don't know that is true, however the fact that linus has admitted to being shocked by the allegations suggests that a the very least an effective HR exit interview hasn't happened.

If I was running a company, regardless of my position on personal care about my employees wellbeing, I'd want meetings such as the one in this post a routine. Not only 'when something happens'. I'd want one on one interviews in the cases like this. So that when things like a former employee comes out with allegations like this I'm not shocked, because I already know and tried to deal with them reasonable or I have solid grounds to claim that reasonable effort was undertaken to know these things were happening.

I don't know how it is in Canada, but C suite and board can have personal liability with duty of care to employees in Australia. Ignorance is not generally an excuse for a good reason.