Linus also wants LMG to be about more than him, and a huge part of the controversy is tied to his decision making power overruling everyone else who says they are working too fast.
He could have appeared, that’s fine, but that nobody was able to get him to drop the defensive attitude and just finally say “sorry” without any pity pleas would have been a very strong signal. That they either didn’t think to do that, couldn’t get Linus to agree or don’t have the power to force him also sends a strong signal in the other direction.
What source are you looking for, exactly? You asked about a specific incident and got a fine summary. If you want more context, it’s very easy to find.
If you are looking for a “source” for a subjective opinion of someone’s personality… I don’t even know what that would accomplish or what form you think that would take.