I believe I'm having an owl glitch (not THE owl glitch), looking for advice.
I found two of the owls (I believe by the cabin and waterfall), then turned the game off. Came back and found the last two owls and headed for the giant statue. I know I found all four because I wrote down their quotes as I found them.
When I got to the Owl Statue, only two of the owls were there. I figured something went wrong with the save, so I went looking for the owls again. I did find the one by the Windmill a second time, and now he appears at the owl statue, but now I've waited all night at the other 3 locations and no fourth owl.