Mean while check this KB
Hope this helps kindly mark this answer as correct or helpful so that it will help others
Unfortunately, neither of those links will help with this issue. The second one has someone essentially asking the same question I am at the bottom of the thread.
Please go through a small workbook I attached. Dropped measure Score on filter for All Values > Special and then selected Non_null Values. It helped to make Blank/Null values in Table with out color. Is this what you are looking at? Let me know.
You are using individual measures. I am using Measure Names/Values. Unfortunately, I have a hard requirement to keep both Measure Names/Values and Split Color Legend as there are two many columns in this particular detail view.
Your solution does not work in this case. But thanks for the tip.