What's odd is that this half-session, to the best of the knowledge of everyone I've discussed this with, was not part of the later Roulette contract that Lee never got around to fulfilling. It stands out as an oddity.
This being said, I do not claim to have done extensive research on this, just talked to a few people in the music business and a couple of Morgan and Dameron biographers, so perhaps some information has been uncovered by others since that would clear this all up.
Bertrand.