Do you match any descendants of Cason Scott???
I have the will for William Scott who died 1793. There are a lot of William Scotts who could be sons of this William and yours in Williamsburg is further away than some of them. Do you know of any male descendants of your line? yDNA would be a big help. William is a very common name in the Scotts. Benjamin, not so much. We have a sample for Benjamin Scott of Richland/Fairfield County for comparison and since there are not many Benjamin Scotts, I think it most likely to try to tie your William to him with DNA.
I suspect that my ancestor, George Scott, was a brother to the William Scott that died in 1793.