Deconstructing Let's Dance On - The Monkees (Isolated Tracks) 

Yes, famously omitted 😂

It's always been a mystery because Larry Taylor was present at the session. Boyce & Hart also recorded the backing tracks to the album version of "(Theme From) The Monkees" and "This Just Doesn't Seem To Be My Day" the same day.

I read somewhere that the bass player arrived late for the session and everyone else had already recorded the song.

Even if not, they could have done a reduction mix.