Well, no ... it wasn't the "failed rescue" that led to his death. It was the fact that he went into the cave in the first place.
When accidents happen, they can be fatal.
Accidents are lot more likely to happen to -- and to kill -- inexperienced spelunkers traversing tight non-horizontal spaces far underground.
Don't get me wrong. I'm not trying to blame the victim here. I don't think that there's any need to blame anyone. ACCIDENTS HAPPEN and they don't have to be someone's "fault."
If we're going to blame someone, let's not blame the rescuers who spent 27 hours -- quite likely at significant risk to themselves in that same environment -- trying to get the guy out of a situation he got himself into, okay?