I don't know where you are in this case, I am still on thread 1, reading and taking notes, but I wanted to put this out there and I hope it doesn't derail anyone. And sorry if it's been suggested, but bear with me.
The dentals are weird. Very weird. She had fillings in all her back teeth, which points to lax dental care at one time. He had a mouth full of dental work, the expensive kind that has to be done after a lot of dental neglect.
Someone spent a lot of money on their teeth, or rather, their appearances. He did still have that bad tooth, but it only would have been visible when he smiled, if I am picturing it right.
They had their jewelry, gold watch, flashy rings, items that reek of wealth, yet inexpensive clothing. Doesn't mean much, but in perspective...
Also, her jewelry was reported as being considered "costume". More appearances.
The almost mafia style in which they were killed, with the lack of sexual assault.
The fact that they seem to be wealthy, yet were never reported. (As far as anyone can tell, at this point.)
The fact that their killer did not seem to be concerned with the matches in the man's pocket, yet they had no cash and no ID. (Do we have any indication that the pockets were gone through after death?)
The story about his father being a Canadian doctor, which sounds like something pulled off a mystery movie, and I don't buy for a second, but does show they had well rehearsed stories about who they were and from there they came. IMO.
The manner in which they were killed and dumped, minimal time, minimal effort.
Working theory, and I ran this by a friend at INTERPOL, she thinks it possible, given the practices of the day, these two may have been recruiters, either for drugs or prostitution.
The country was in a state of celebration, those that even bothered to have their guard up at the time, had dropped it a little. Both Does had someone sink a lot of work and cash into their appearances.
I don't believe that they were wealthy, I think they just had to give the impression, it was their job. Think about where we know they were: the coast, FL, truck stops in the Midwest, all places where runaways congregate. I believe they may have been looking for just those runaways.
They may have been recruiting drug mules, they may have been recruiting for prostitution either here or abroad, but I am 99%, based on what we have about them, that this is what they were doing.
They either were not producing the required numbers, or they tried to run, or they didn't bring in the amount of product that they were supposed to, but I am sure that it was an illegal employment situation, and their employer killed them.
The party that I talked to at INTERPOL said that today, you don't see as many recruiters, most of the time, those in the drug or sex trade, especially those going overseas, are not coerced, they are simply forced, but in 1975, it would have been much more common for the pimps and dealers to have a couple people on the payroll that did nothing but look good, talk a lot, and bring more people into the organization. She also said that these two would have fit the profile and their murder would have fit the profile of a cartel or sex ring. It also would explain to her why they have lain with no names for as long as they have. She even went far enough as to say that the matches could have been left simply because the killer saw no reason to go through their pockets. It's very likely that the only money they received, they got from their employer, or handler stateside. They never would have had ID in the first place.
None of this makes them any less victims in my mind, they were young people, and were very possibly escaping bad situations of their own, but I have wracked my brains and nothing else fits. And, you know, me and zebras.
