Earlier quoted context omitted.
and they'll all think that you are the problem. Agreed.
The thing is that often they are right. It's almost literally crazy to me that he wouldn't just try to reschedule the meeting and that he would work when his grandma was dying. It's not working long hours that's a problem but in my experience it often correlates with people who don't work well in a team (which this guy seems like a perfect example of).
This dude, and many people I've met similar to him, takes people on their word and acts accordingly. He might be a bad fit for an environment where this is not respected, but I'd argue this is not a sign of 'not working well in a team'. Rather, it's a sign of him taking people on their word and finding it difficult to work on a team where this is not respected.
I imagine there are plenty of teams, in companies big and small, that do respect these kinds of things. Or at least do so begrudgingly.
My personal experience is that any work environment that does not manage to handle these 'your word is your word' type situations, even if badly, is a horrible place and destined to fail (barring some exceptional situation where they can get away with it).
Outliers like this particular person are a kind of anchor-point. Perhaps it's okay, even necessary, that they don't quite thrive in certain stages of a company. But when they actively flee the ship, it's a horribly sign.