Well I don't think that's far fetched as far as being backlit. Because anyone who camps knows that happens. You can see people outlined if they turn on a light.
But that means someone was waiting all night with a high-powered rifle or something for him to turn on a light in the tent, right?
I mean that part seems less probable than someone who has tracked him or knows he is there who creeps up, opens the tent and shoots him dead.
Of course if someone does that they also have to either have a light so they can see him to target him, and be more likely to be seen, or have night vision.
One thing for me points to this being more possibly a hit- he was shot in the head.
If this was a random guy taking potshots, what are the odds of being that accurate? What are the odds of actually striking someone in the head and killing them? Probability wise (and I'm bad at math, so not sure), if it was a pot shooter type who just liked to scare or threaten people, wouldn't the odds of an accidental or even reckless direct hit to the head be greater if there were many more shootings than 7?
And if it is a serial shooter, intending to kill, wouldn't there be more deaths?
How do these shootings compare to other cases?