Imagine, the real Delphi killer is someone, who stalks not only teenage girls (online), but perhaps also their surroundings, in which they live. He might find for example JBC (or/and DN and so on) on the net and personal data as well as the living circumstances: family history, education, jobs, leisure activities, criminal record/s, whereabouts. The real killer chooses JBC plus some other men for being well matching future suspects, if a crime (abduction, murder) would happen in their area, preferably a park/nature reserve/lake/creek/wood. Imagine, the real killer in his mind combines the well matching "suspects" with online chosen victims (teenage girls, one or two) and now he plans, where to go next for his murder mission. Further step would be to scout a certain terrain, online and at least once in person. Last step by the killer would be: to reach his goal in letting the crime happen like depicted in his killing fantasies. The murderer flees unrecognized, and afterwards it unfolds just as planned, namely police are overwhelmed with a huge outdoor terrain and many possible, well matching suspects. Crimestoppers is getting 40.000 calls/mails - nearly impossible to deal with, also taking into account human fallibility. Video/audio or not - due to clever preparations for the crime (disguise of voice and body/head) afterwards the way is now again open for hiding in plain sight and being a normal, respected citizen like before. Until the next crime in another state or the same state once more.
Years ago I wouldn't have had these ideas, but now in 2021 they have gradually expanded. There must be a certain reason, why there are numerous men living in the area, which could very well be the suspect and turn out as being not the right one.
JBC II and what we know about him seems to be a match. But I'm not sure, if he indeed is the one or if he is one of those "guys", who the real killer had in mind, when "creating" a double murder scenario, this time in Delphi. (Who knows, where he did the same or similar before.)
If JBC is the evil monster also from Delphi, I will be fairly surprised. Though to be wrong all the time is no problem, as long as the killer is caught finally. 4 years waiting for it, is actually too much.