If he hadn’t been in custody, Nelson would have a hard time believing Israel Keyes actually existed.
Again, Keyes was very clever. His parents would move the family ever few months and live out of tents. My assumption is that he was a survivalist at ab early age. Keyes was also in the U.S. Army and was apparently candidate for the Rangers. I have a relative who had similar training. Keyes knew what it took to hide his tracks and keep investigators guessing.