This is my first time ever hearing about this case. From the recording, what I took away from it, was that Brandon's car ran out of gas, and he stumbled upon something he should not have been around. I feel like before he says "I accidentally ran into 'em", he says something along the lines of "There was one guy talking to him". When he says "I accidentally ran into 'em", I think he means "ran into them", as in meeting someone. Like "I ran into Jane at the grocery store". If someone was out there, let's say, doing something involving drugs, and his car ran out of gas, and he was kind of walking around the area a little waiting for someone to show up with gas, he may have come across something he shouldn't have. There was no damage to his car, so I don't think he "ran into" anything in that sense. I also think when he says he hit someone, he is saying he hit them as in punched them. I don't think he is saying taken or pushed into the woods, I think he is saying chased. I also think he crossed the road at some point, he references "both sides of the road".
So the scenario I am imagining here is that Brandon "ran into" some people or a situation that he was never supposed to see. They came at him aggressively, so he hit them/someone, and then took off running. He was chased into the "woods", where he hid and made that 911 call. That's why he was out of breath. After the 911 call, he was injured (maybe whoever was chasing him found him), and that is where the later call of "Im bleeding" comes in. I don't think the "yeah" was another person. I think it was Brandon. It sounds like he was looking away from the phone, and not paying attention to what the dispatcher was saying. I think he was looking behind or around him to see if whoever was chasing him was close. So he distractedly, looking around, says "yeah", then his brain catches up to what was asked and he says (in a more focused tone) "No, I need the cops".
I think Brandon was hurt by someone out there, and his body was taken by that person and hidden. If someone else was out there, they had to have a mode of transportation. Why were no tracks found? Either foot prints or tire tracks? What is the ground like out there, would it hold a trail like that?