In the film Wind River (2017), the key sign that led Cory Lambert and Jane Banner to the body of Matt Rayburn was a sled track that went from the Littlefeather's house up into the mountain. According to Cory, somebody unloaded a sled at the Littlefeather's house, drove up into the mountain and never returned, because there was no tracks coming back. Who left these tracks and why was Matt Rayburn's body by these tracks, if he was killed at the drill site?
I was confused by the whole track thing too, so I had to rewatch it.
Like you said, Cory said someone unloaded the sled then took a one way trip. I believe it was the security crew, unloading by the druggies' shack because they knew Matt's GF was that dude's sister, so they rode from there in an attempt to make it look like her brother killed Matt and dumped his body.
What doesn't really make sense is that they should have then turned around and came back the way they came rather than ride right to the drill site. It seems to me that if they were smart enough to plan the body dump, they wouldn't have just continued riding to the site, but I chalk it up to them thinking the tracks would get lost/covered in the thick areas that Cory ended up walking. I think he did lose the track, then saw the lion tracks so then followed those since that was his actual job, then just happened to pick the sled track up again at the den.