I figured out what controls luminance but never figured out what combination of adjustments would make it respectable. CBB, CRR, CBG, CRG (movie) is what you would adjust but they have a weird interactive behavior. If your overall Delta E's 94 are below 3, I would not worry about it.
The Delta E's in HCFR for Greyscale and Colors are shown in the attached image. I am not sure if these are Delta E 94 values. Can you enlighten me (no pun intended).