I hunt, so I'll weigh in. I'm not the apologist you're probably looking for, though.
This guy, obviously, did some stupid things. First off, he shot a person, so obviously he had no fucking clue what he was aiming at. Secondly, it was after sunset, which comes depressingly early this time of year, so even if he knew what he was aiming at, his vision would have been reduced due to the lack of light. Third, he was trespassing, which is so stupid in its own right and I have no clue why people do it. Fourthly, he wasn't even out in a stand actively hunting; he just said he thought he saw a deer so boom let's go chase it. What a moron. Finally, he was shooting near people, but given the other things, he obviously doesn't care that he was being stupid, so you get the point.
I will say two things that you can argue about:
First off, there is absolutely no test of any kind when offering someone the chance to legally hunt, carry or own a weapon, or shoot a gun that will prevent this sort of thing. In order to get your permit and your tags, you have to go through a hunter safety class, and all of the dumb things this guy did are very clearly covered. You could give someone an IQ test or a mental health exam and you wouldn't know ahead of time of anything like this. You could try a background check before giving them a gun and there would be no indication that this guy is this dumb. You could put him on a range and see whether or not he knows how to shoot and you still wouldn't know that this guy is this dumb. The fact of the matter is that stupid people exist, and sometimes stupid people get their hands on things, like guns, that make their stupidity a much bigger problem than it otherwise would be.
Second, if this cocksucker of a hunter is what you think all, or most, or any more than a select few hunters out there are like, you're out of your mind and need to get to know some hunters. I hunt for food and in order to partake in conservation measures against deer populations going out of control - I don't care about antler sheds (though a nice buck is a nice buck). I just want to eat good meat that I only get a few times a year and do something good for the natural world that might in some small way help repair the harm we have done to it. Many hunters want their rewards or their trophies, but the deer get eaten and they do everything cautiously and with the utmost regard to safety. Kids where I grew up learned how to properly use and handle guns when they were young on ranges and learned how to hunt with a responsible adult by their side walking them through it, which is exactly how it should be. I shot my first 10 gauge when I was 11 and my first rifle not long after and I was a late bloomer. You can debate the right age to start kids off on that track all you want, but the fact is that this guy deliberately went against everything that the incredibly vast majority of hunters have drilled into their heads from the moment they start hunting in the first place.
He deserves to be in prison for manslaughter at the very, very least. Tack on a trespassing charge and something about illegal use of a firearm after dark. Make it a big enough fine to pay her funeral expenses. Throw the book at him.