The DAR genealogical database is now open to the public. If you search for the DAR page, enter it and click on the library page. You'll find the database as a link on the left. I wish it had been available to the public when I was doing my research! It took me five years to prove my lineage on my father's side. It took me two hours of research on the DAR site to find my mother's lineage to join!
That being said, it looks like both Thomas Jr. and Sr. have been discontinued as DAR patriots (in the official sense) because more proof needs to be found for their service. Thomas Sr.'s records have even more issues. I have been told that early ancestors were not as "vetted" as those who have been accepted more recently. I had an ancestor on my mother's side disallowed---he had a common name, and it seemed as though the "patriot" was a composite of two men who had the same common name.
I have Lindley ancestry, as well as Abercrombie, Sims, Babb and Kellett. I entered the DAR via the Sims-Babb-Kellett link. Mary Lindley and Colville Abercrombie were in my direct line---one daughter married a Sims, and the other a Babb. The Babb offspring married her Sims first cousin. Hard to keep them all straight.