The only reason I tend to think they planned a meetup with somebody is that on day one, police said to be aware of what your kids are up to. I bet we won't hear this bit of info until this goes to trial.
Yeah, that stuck out to me too. Tremendously.
It's easier to think this is some experienced old SK drifter but I'm having trouble with that due to, IMHO:
1) The outfit and body type look like typical-rural twenty-somethings to me. I absolutely do not see an older man. Those aren't Mom jeans - they are Wrangler or Lee or Carhart loose jeans young working men wear if they are doing physical labor or are a bit overweight.
2) The perp is clean and looks groomed, maybe inclusive of a young-man's chin beard.
3) The perp photo is on the southeast end of the bridge, right? Yet the girls were found on the north side of Deer Creek. I almost have to wonder if the initial SE bridge photo was just taken in wondering about who the guy was or if he was in the background when Libby was taking photos of Abby on the SE end. Somehow, everyone ended up back on the NW entry point, then down the hill to the creek.
4) The audio I hear, and the words of the presser, are just "down the hill." It possibly is not a command, but a directional guidance.
5) The school day off was just local to Carroll County, right? Please correct me if I'm wrong. But Feb 13 was not a Purdue snow day or even a snow day off from other counties, right? So either the clean BG just happened to be there, on a Monday, and was trolling for kids to murder, or he knew kids would be there because of the unique-to-Carroll County day off from school.