I haven't worked on the LCT records for a while. The 1820 census shows two at least two different George families. One family consisted of Benjamin, James, Thomas, Richard, and William (pp. 35-37). Jesse and Pressley were in a different group, listed on pp.46-47. I don't know which group John, listed on p. 42 was associated with, but there was a John associated with the first group and noted in earlier land records. Benjamin was my 3rd great-grandfather. I have tracked the groups through circumstantial evidence. Your William George, noted on page 72 of the 1850 census, is probably part of this group, either a newphew or cousin of Benjamin. There are a number of researchers looking into the George families in LCT. I would not doubt that someone has more solid research delineating some of these later branches.
I believe that Benjamin was descended from Col. John George. I have good circumstantial evidence, but haven't found real proof yet. A rough draft of this research is posted on the George Surname Study web page:
In addition, the DNA research portion of the George Surname Study has information which shows that the Benjamin, James, Thomas group and the Jesse, Pressley group were not closely related. We originally assumed a connection because both groups were in Wilson County, TN, at the same time, and moved to LCT about the same time.