Awesome find! I’m not 100% sure but I believe he played on all the tracks but the first one (the title track which had a different producer and was recorded in Nashville on a different date from the rest).

From the album’s Discogs Page:

connorman1995 May 25, 2017
referencing Singer Of Sad Songs, LP, LSP 4418

Recorded October 29, 1969 RCA Victor Studio, Nashville
Guitar: Fred Carter, Dale Sellers, and or Chip Young
Bass: Roy Huskey
Drums: Kenneth Buttrey
Piano: Hargus "Pig" Robbins
Harmonica, organ, marimba: Charlie McCoy
Vocals: James Cason, Sandra Robinson, Bergen White

December 17, 18, 19, 1969 RCA Victor Studio, 6363 Sunset Blvd., Hollywood, CA.
Guitar: Donald Owens, Allen Kemp
Guitar, fiddle: Sonny Curtis
Bass: Randall Meisner
Harmonica: Carl Walden
Drums: Patric Shanahan
Piano, harpsichord: Don Randi
Vocals:
Dorothy DeLeonibus, Hoyt Hawkins, Neal Matthews, Gordon Stocker, Raymond Walker

I continue to be impressed by Mr. Meisner.