It probably could be adjusted because in VFB+, I could have LUT, Tonemapping and WhiteBalance working correctly at same time, neither clamping each other.
Currently the WB is rendered unusable, because only no WB (6500/White) renders correct image. Everything else is like white-balancing clamped jpeg.
I don't see why this is LUT vs WB, both can work correctly together just fine, as illustrated by VFB+ .