I think there's a possibility that Leigh is the UID and I agree the most probable scenario is that he was robbed and killed and his car was used to dispose of the body, maybe in the ocean or swamps (there's a lot of both in the 250 miles between Orange City and Boca Raton).
I agree that the "full set" of dentures makes it unlikely to be a match but consider the following:
1. My father has upper and lower dental plates plus three or four teeth that have had some work done to retain them. (He was born ~2 years after Leigh). He therefore has a virtually full set of dentures as well as some teeth.
I might (carelessly) describe him as having a full set of dentures - and would there even be any need to obtain dental records until there was a body to compare against?
2. The body was only
5 miles from Leigh's home and in the same county. Logically this should have been a comparison and rule out regardless. Has it been done?
3. Leigh is a pretty big guy for someone of his age. He's relatively tall and heavy - my grandfather was that kind of build at that age and he really stood out as a larger man in his generation. We also know that the UID was probably fairly elderly due to the advanced arthritis and, based on the clothing, heavily built.
4. The decedent probably drove to somewhere relatively near the site of his death. His vehicle may or may not have been located. It may have gone unclaimed in a pound or it may have been stolen. Leigh could have driven himself to Boca Raton before disappearing, but equally the car could have been stolen from Volusia County and driven to or fenced further south.
5. The POI is named
here and there is more background about the case. The case is circumstantial only, though it does appear quite strong on the face of it. Briefly a named POI, who is known to have operated in the area, confessed to killing "somoeone" at Smyra Beach (where Leigh disappeared) and matches the description of a person seen nearby. Unspecified evidence was located in the recovered vehicle a year after the disappearance.
6. The presence of a gun at the scene does not prove a suicide. If he was a fisherman, Leigh could also have been a hunter... could he have kept the gun in the car and that was used against him? Dump the body and the gun together and you have a convincing suicide, especially if the body isn't found for 4+ years!
7. Very little investigative work appears to have been done in relation to the UID. Bone density, fusion, etc., ought to indicate a skeletal age within a range of 20 years or 60+. 25-99 years basically says that this is a mature adult with signs of age-related degeneration, however slight. Therefore many people could match... so how many have been compared? Within the limited physical description, Leigh is a pretty good fit in terms of height, weight and age (although I tend to think that the weight is probably hypothesized based on the clothes found, given how sparse the rest of the description is).
