JR Monterose told me they did record a second date, and it was better than the first (musicians often claim their unissued work is better than the material you can hear ). Cuscuna is a HUGE KD fan and the second date was high on his priority list when he got in the ABC vaults over 25 years ago, but he assured me it was lost.
Mike is such a fan he hired KD to play his high school prom. If he says the stuff is rejected (an unissuable), I'd take his word for it. KD had chops problems around this time and Charles Davis's intonation is always a "sometime thing". Everyone else in the band had personality/substance problems - looks like a recipe for a bummer to me.
Sometimes producers protect artists' reputations by not releasing the stuff in spite of fans "right to make their own decisions". I respect this. I understand why writers burn manuscripts.