Werent the previously released discs all re-recordings except for the CAGE and Where No Man discs???
No, all of the GNP Crescendo releases of TOS scores were from the original recordings -- Volume 1 with the two pilots, Volume 2 containing "The Doomsday Machine" and "Amok Time," Volume 3 containing "Shore Leave" and "The Naked Time," and the TOS portions of the two Best of Star Trek
albums -- Volume 1 containing the main title and a "Trouble With Tribbles" suite, and Vol. 2 containing a different main title arrangement by Fred Steiner (actually I think it was the end title version) plus suites from "The Corbomite Maneuver," "Balance of Terror," and "What are Little Girls Made Of," plus a "lounge mix" of the main title which was used as source music in a couple of episodes.
Only the two Varese Sarabande releases conducted by Fred Steiner and the two Label X releases conducted by Tony Bremner are re-recordings -- although there are probably a few TOS tracks on the SF-themed albums the Cincinnati Pops Orchestra released back in the '80s/'90s.