They ask what could fairly be judged to be the bleeding obvious to see how people might expand on it as you would have to in an essay whether you think it necessary or not. They might like 'What ifs?' to poke holes in assumptions. Hey I don't say it's right rather than going with what's in the question and not bothering mentioning what's not...
'Killing' is a verb , the act of causing the death of someone. It arguably carries more connotations of deliberateness than 'killed' would. 'You killed him!' might suggest surprise at what could have been merely a manslaughter rather than premeditated murder.
But 'You were involved in the killing of him' makes it sound more like a premeditated plot (even tough it doesn't have to be). In this particular case we are not told whether the man was accidentally or deliberately shot. It is merely the choice of the word 'killing' that suggests deliberateness yet that does not necessarily have to be the case. If the man had been 'run over' instead of 'shot' perhaps we might have thought it more likely to have been accidental. To shoot someone you generally have to be holding something that is specifically designed to kill or injure. It might seem that I digress but the choice of the word 'killing' can, if you look at it one way, be regarded as important.
You only become fully, defiinitely, regarded as 'killed' when the moment of death arrives - which happened in New Hampshire in this case. For the 3 days that the victim was still alive, the consequences of what we later call the 'killing' might still be happening (and we can call those consequences themselves part of the killing if we like) but they have not yet been 'killed'- not if the medical team can have anything to do about it.
He died of his wounds but what if? What if the wound was actually relatively minor and a competent medical team should have easily been able to save him? What if he dies 'of his wounds', it is recorded, but the actuality is that the medical team knowingly left his wound completely open in a ward knowingly full of dangerous airborne particles? You might say 'Yes but if he hadn't been shot he wouldn't have been there in that position in the first place'. But would you blame someone who accidentally knocked out another person's tooth in a sports game when the injured person died due to clear negligence by the dentist who was supposed to be fixing the tooth?
The question is where did the 'killing' happen? Not 'where did the shot happen?' nor 'Where did the man die?' The answers to those are already evident in the question.
Three days elapse between the shot and the death.
Do most people assume that 'shot' must mean 'gunshot'? What if it is referring to a photo shoot? The man might have already had those wounds prior to the photo shoot. A magazine might have been taking photos of his injuries! We make an assumption if we think that the word 'shot' and the phrase 'dies of his wounds' are in any way linked except that they happened to the same person.
Even if it is a physical injury kind of shot, it does not necessarily have to be a lead bullet or from a gun.
But I might be tempted to digress too much here. If it was a physical injury kind of shot and if it caused the wounds then it doesn't matter what he was shot with.
If we assume that it is a gun shot and that the gun shot caused those wounds and that the medical team were not so incompetent that it was their actions that caused the fatal harm to the inside of his wound then it would be fair to say that the killing happened in Texas. That's where the action of causing the wound happened. When we say that someone has died of their wounds we do not imply in that that the victim's body has betrayed them in any particular way. It's not like we think that the victim's immune system of it's own free will thought 'Nah f*** him'. So, unless there is other compelling evidence, we do not think that any aspect of the 'killing ' happened in New Hampshire. It happened in Texas.