When I try to understand something like this, I don't immediately search sex offenders in the area. My instinct is to understand the crime scene and how the suspect moved through the crime scene. In this case, the crime scene extends from the North entrance of the park to the cemetery, and the SE end of the bridge. My next curiosity is how he would have looked after committing the murders. I think he had wet feet.
If this is the same suspect, I have to wonder why there's a 20 mile distance between abduction and bodies in 2012, and less than a mile between abduction and bodies in 2017. Got away with it, getting careless, doing it closer to home, giving more away by accident?