Of course it's Lemon. He's singing in his Deacon L J Bates voice, which is pitched a little differently from the majority of his blues records -- a bit deeper, since the higher-pitched sexual insinuation of a blues singer was not considered appropriate for religious songs. Three or four of BLJ's records appeared under the Bates name.

Lemon recorded the song twice for Paramount. The first take, 10/1927, was issued under the Bates name (the flip side was "Where Shall I Be?"). NB that the next song in the session was "One Dime Blues," which uses the exact same guitar part. (Lemon also used it for "Prison Cell Blues," cut a few days after the remake of "Grave.")

He recorded "Grave" again, 2/1928, and this time it was released under his own name, with a standard blues on the reverse. I don't know which version is on your album; I'm not even sure which is the one I have, since both my LP versions are transferred from the Folkways Anthology (I don't have it or the notes). The one I have on mp3 sounds like the one from the Anthology. The Bates 78 was Paramount 12585, while the BLJ 78 was Paramount 12608 (also issued on Broadway 5059).