Suicide is my take too, but deeper study will have to be done to confirm your inside conclusions.
I’ve been researching suicide/homicide for something I’m working on. Professionals think it is a whole lot more common than we know. Mostly unreported. Many supposed road rage accidents are exactly that. And, one car accidents where the driver and the object of his rage are present. A combination of homicidal rage and self loathing at a suicidal level. It is also an exercise in power by those feeling powerless. I don’t think there are many things more powerful than a speeding train. Or many things more self-loathsome than a homosexual.
What more likely candidate than this loser?