The new survivor and killer's backstories seem to be heavily intertwined.
First off for Jeff, "A late-night regular noticed his sketches and asked him to do some artwork for his gang up Mount Ormond. Jeff accepted the challenge and painted a large mural depicting 'the legion'" For me, this is pretty obvious that this is Frank asking him to make a mural for his group of friends. (Given their name is literally the legion, and it was for a group of friends who would hang out up at mount Ormond) "Driving by his former high school, he remembered the mural he painted up Mount Ormond. He bought a 12-pack and headed to the lodge." This one seems to be pretty heavily linked to this quote from The legion's backstory "Frank spotted something moving through the woods. He grabbed his knife and broke from the group to check it out." I theorize that it's Jeff he sees moving through the woods, this means that the entity would have gotten all 5 of them at pretty much the same time. If this is right, I think this is the most intertwined a killer (Or killers depending on how you look at it) and survivor have been, at least for the original characters.