This is truly the case with the Ohio Jidokwan Karate Association and their descendant, the American Jidokwan Karate Association. This is not to be confused with our American Jidokwan Association, an organization that is an official representative of the Jidokwan Headquarters in Korea (or any other organization using the name American Jidokwan), but I'll get to that shortly.
From Robert Moore's official biography:
"Robert C. Moore, 3rd Degree Black Belt, began his formal training in the school of Ji Do Kwan (Kong Su Do), in Chun Chon, Korea during an overseas assignment with the US Army in March,1962. His teacher was Mr. Nam K. Yun, 3rd Degree Black Belt and his training was directly supervised by Dr. Kwai Byeong Yun, 8th. Degree Black Belt."
Some sources say that Moore actually only achieved a 1st Dan in Korea, and that his 3rd Dan was actually awarded by Robert Trias of the US Karate Association, but for the purpose of this article we'll give him the benefit of the doubt. For those familiar with Jidokwan history, Kwai Byeong Yun was the President of Jidokwan from 1950-1961. Any rank issued or overseen by him must be considered legitimate rank. All good so far, but that's about where the legitimacy stops.