It would be difficult to control two fit active teenagers without a weapon, at any point one or both of them could have run away at speed, the picture of the suspect to me does not show someone who could have easily chased them both and caught them if they ran,
odd that LE dropped into the presser could have been a crime of opportunity but also could have been somebody who knew the girls were going to hike in that area, possibly suggestive that they are looking at the possibilty one or both girls were chosen pre the murders,
this then leads into how many people knew the girls were going to that area that day at that time, and did the girls post on one or more social media platforms the plans for the day,
to murder two victims in one attack takes alot of confidence and control, especially in the area they were, they were not confined in a room or a building so he had to take the girls to his chosen place and carry out the attack and get out of their undetected,
to me it also shows familiarity with the area and terrain,