I don't know your experiences in this and again this is meant with respect due but unless he's an emo snowflake it was something serious from the wife.
I've been up to my eyeballs in work stress, lawsuits etc and nothing affected me like my wife's threats. Nothing.
So maybe I'm drawing on personal experience and recency bias but I've done a heck of a lot of meditation and soul searching on this and I just don't believe it was because of a coup attempt gone badly. You wouldn't even mention your wife and family in that scenario, perhaps one as a parting statement, but not at the level he fell on his sword.
I've been in this situation where kids and money fuck up a lot in a relationship where one spouse is being ignored and I'll fully admit my fault in diving into work to build something for us and not balancing it properly.
I now try to warn workaholics of this.
Sure it's speculating but I've now watched both pressers three times and what I see is Shanahan thinking its all business because he does not know the severity of the cost on Kyle's marriage with everything and why would he know? Its not something you tell your boss, that you're distracted from your job.
Shanahan believed what he said, so did Dubas, what they didn't do was talk about the exact same thing. One was business, the other was both business and personal.
People rely on occams razor but the razor really says to start from the smallest amount of variables and go from there. I did that and the extraneous information given, especially by Kyle, leads me to believe there's more to it.