Mordecai Williams connects to Thomas Martin and the Shells. Mordecai's wife was Thomas Martin's daughter. Thomas has an estate record in Burke and they are mentioned in John Shells rev war app which you can read if you have a fold3 account.

Thomas Martin's estate record can be viewed and downloaded at familysearch.org link below

https://familysearch.org/pal:/MM9.3.1/TH-1951-26684-35141-25...