I think she was known to the perp. It seems that if there were a digital footprint (cyberstalking, catfishing, online communication, etc.) then there would be some indication from LE. Maybe not, of course, but that's just not a feel I am getting right now. However, I am not ruling out the idea that he was quietly stalking her. He might not have been contacting her online, for instance, but he could have been the relative or friend of someone she knewandable to follow her that way. Even if HER posts were set to "private", he'd still be able to see if she commented on a mutual friend's stuff, or if she made comments to a group they both belonged to. I've met several people in "real life" who, upon meeting me, have said, "Oh, I've seen your posts and your comments when you comment on _____(mutual friend's) stuff." So I would be looking at friends and family members of people that she was connected to both online and in person; ie, a friend's father, a cousin who was hanging around a girlfriend, an older friend's ex boyfriend, etc. I think this was someone who definitely knew HER.
Elizabeth Shoaf was kidnapped and held in an underground bunker for 2 weeks. The man who took her simply wanted a young woman and it was her bad luck to be there in the vicinity when he took someone. I don't think this was the case with Jayme, though. I think he targeted her.