Apologies, pepper.
Please change the word DID to the word WOULD, as in how WOULD you pull such a scam off? Such a difference a single word makes.
To my mind, IF there was a scam it started around 1795. The Colonel Robert in charge of the Onslow Co seemed to be the family patriarch, well off financially, well established in his community (and a judge?). This does not seem like a person who would risk his reputation for a deliberate hoax, so he was a believer (at least in the possibility).
So...IF there was a scam, it began upstream with the original three, or Simeon Lynds, or a guy who sold the three a map?
Scams are usually concocted to make money, so questions remain - who got the money, and how was it done?