Maybe, it would be helpful to have another map, this time of the piece of land where the Iowa cousin's E/L were found dead?
I usually search google images, websleuth postings often turn up there too.
https://www.websleuths.com/forums/s...sdale-13-July-2012-37&p=11893296#post11893296
In both cases the girls bodies were left not far from a creek.
It's possible the look and feel of the location where the bodies would be found, was important to the killer, perhaps related to a memory or fantasy. I've heard some killers 'stage' the bodies for discovery.