I have been listening and learning to play for about 3 weeks Dave van Ronk's great version of "Just A Closer Walk With Thee" from the recent Smithsonian/Folkways collection of his first two albums. Dick Rosmini is credited with the backup and the 12/8 fill, and Dave says nice things about him in the new liner notes. I don't have the album with me at the moment, or I would give you the reference. I assume he played on a lot of other people's albums, so this may not interest you.
yours, Peter T.