That is because Griffin was under contract with Riverside at the time, and Davis with Prestige.
Davis helped a lot to start Scott's career. They first recorded for King in 1956, then for Roulette and Roost. They did a lot more sessions for Prestige, the Craft box collects only the "Cookbook" albums from June 20, September 12, and December 5, 1958.
The European budget label Solar Records did this years ago, fitting all on only three CDs inluding a bonus LP - Craft limits each CD to the "original album". I will probably buy the Craft boy as I expect excellent sound, but they could have done a real big box and cover it all. At least they added the alternate take from the first session that was on on the OJC reissues. But the three sessions resulted in 34 takes - the box has only 26, missing the equivalent of another LP! Can't they do it right?