Tears At the End of A Love Affair - Tammi & Marvin - 1968?

[carole cucumber]

I also ran across this entry of Tears at the End of a Love Affair on DFTMC. Anyone know any details behind this one? Was it started and not completed? Did Marvin ever add his vocals?

Tears At The End Of A Love Affair [[Harvey Fuqua-John Bristol-Sylvia Moy) publ. Jobete
Marvin Gaye & Tammi Terrell; recorded Hitsville-GW, completed 05-Mar-68 ; produced by Harvey Fuqua, Johnny Bristol ; [MPG mistake in odb]
12-Mar-68 [acetate]; LP [[M): Q-HEM-0164/5-FNDD

Tammi Terrell; recorded Hitsville, completed 12-May-66 ; produced by Harvey Fuqua, Johnny Bristol
25-May-66 [acetate]; 45 [[M): CCMN 0972-NHDD [with horns]
May-66 [acetate]; 45 [[M): CCMN 0306-NHDD
Jan-69; LP [[S): Motown S652 Irresistible
1991; CD [[S): Motown MOTD 5231 Irresistible
16-Jul-01; CD [[S): Spectrum 544 491 2 The Essential Collection [UK]
01-Oct-10; CD [[S): Hip-O Select B0014792-02 Come On And See Me: The Complete Solo Collection

I'm curious... what does this annotation [MPG mistake in odb] mean?
MPG, the album or MPG , Marvin's initials? And what does odb stand for?