Such kind of situations do not really count as guro because guro must have some erotic context.

Sure we can use non guro content as guro but in that care we repurpose it. There is no reason why you cant jerk off on 9/11 victims, school shootings or traffic accidents. but it is not as good as events that are already in the sexual context of some sort.

as for example if a couple is having sex in the car and then tree falls on them so that the branch skewers them both while that guy cums inher pussy, will be way more erotic than if same couple is driving on the highway and gets into traffic accident. But if the traffic accident when girl is trying to show her tits to the guy then it counts as guro.

So to create guro situation you should first set some kind of erotic mood and then something can happen