Lots of people seem to have a need to touch a glowing stove before they’ll believe it’s hot.
Your cow-orker seems to be someone who believes it necessary to jump into a bubbling pool of lava before he’ll believe it’s hot.
One wonders how many of the other guests at the family gathering are also lava-touchers. If the wife is one, I don’t feel too bad for her.
But if she’s not a denier and was railroaded by family pressure into being exposed, well I hope the husband spends a couple of months hospitalized in abject misery while being told daily of another dead relative he caused. Followed by him going over too. I’m not a believer in afterlife, so it’s essential these people get their complete come-uppance in this one.
It’s not too different from firing a machine gun in a crowded mall*. The harm is palpably foreseeable.
* BTW, does anyone remember what a "crowded mall" is?