I have pinned down "Mr Van Winkle" to two people. Both are sons of Thomas B Van Winkle and Elizabeth Smart. The first, less likely, is Thomas H B b about 1838 MO; a part of a tombstone was found in Spivey Cem LampassasC TX with the initials T B V.
The second, which is most likely, is Andrew Jackson b about 1844 MO. He also was unmarried and is the only one of the 7 sons who had acknowldged Confederate service.
These two are also the only sons without confirmed burial sites.