After days of simply lurking, I decided to create an account so I could post here after my discovery on Facebook.
I found out yesterday that I have a mutual friend with one of DE's relatives. I won't list any names, but DE was on this relative's friends list. Wondering what the connection was between my friend and DE's relative, I found that the relative is friends with multiple people in Galax, VA. I'm not sure what the connection is there, but perhaps she lived in Galax at one point. It seems like there would be some sort of link to Galax if she is friends with multiple people from this relatively small town
Why I think this is significant is because Rt. 89 starts in Galax and leads down into NC, where NL's remains were found. Galax is about 10 minutes from the VA-NC border on Rt. 89. Maybe it's a stretch, but perhaps DE has some sort of connection to Galax through this relative and has been there previously with them, leading to him knowing his way around there a bit.