The only thing that surprises me about this story is that is doesn't happen more often, and closer to home.
Just in my personal experience bow/gun hunting out of a remote cabin in Lincoln county Wisconsin over 10 years, I've lost track of how many close encounters with wolves there's been. Been stalked regularly, sometimes, quietly, sometimes with them howling the whole way, when they do this, they are both paralleling and behind. Been charged head on at full speed, he put the brakes on just feet away, leaves piled up in front of his feet. Had one go into a pounce position close to me, and think about for far too long. Had a group stalk me to my tree stand just before light, they lost me as I went up, at first light I could see they circled around in an organized spread-out line looking for me. They are no joke.
In most of these cases, I figured it was just one small detail that stopped them from going into a kill mode. If a person were to run, look afraid, or be unlucky, I figure it would setoff their instinctual chase mechanism beyond return.
It definitely helps that bowhunters in this state are allowed to carry a sidearm, but they have better night vision than we do. It's just so hard to believe, such a high percentage of people have been so lucky, for so long.