Hinshaw's "American Encyclopedia of Quaker Genealogy", Vol. 5, page 407 shows that a William Johnson, aged 78, died Mar 12, 1835 and was buried at Newberry Meeting at Martinsville, Ohio. This is in Clinton County. It also shows on page 253 that a Watkins Johnson , son of Joseph and Agatha, married Elizabeth Moorman on Oct 30, 1822 at Fairfield. There are 7 listings for Watkins Johnson in the index but none of them show a connection to William, Poly or their sons you named. I had Quaker ancestors in Highland County but not any of these.