I worked at a company where a young black male told his work mates, he was going to kill his girlfriend’s father that night and nobody reported him. He also said that if it went badly, he’d kill himself with fire because he thought that would be an easy way to go. Again, nobody said anything.
That night the father got home and, wearing a mask, he accosted the older, fifty-ish man with a pump .22. The gun got off one shot and then jammed as he tried to load another round. The old man (ten years younger than me now) got the gun away from him and pulled off the mask. The younger man grabbed a knife and chased the father into the yard where the father jumped into a car and locked the doors.
The young man went to a store, bought a gallon of gas in a bucket and went door to door...with a bucket of gas, asking for a match. On the third door someone gave him matches. (Seriously, there’s so much wrong here I don’t know where to begin.) He went out to the mailbox and doused himself with gas and finally got a match to light. It took him three days to die.
As a manager where he worked, I recommended firing the entire work cell who all admitted to foreknowledge of what he said he’d do. But they hired councilors instead.
I relate this story to say that there are other people out there who have this weird idea that lighting yourself on fire is a thing you should consider doing.
Who hired him in the first place? I've worked in places where getting involved in a lunatic's life was nothing but mortal risk and "management" who hired him in the first place wasn't going to do anything about it, especially if the person was of a privileged class.
Report him at your own peril because he'll add you to his hate manifesto and then go after you.
OK, I just gotta know: what line of work were you in?