It may be possible, depending on the specific type of your datasource.
In the example attached in the Forum thread, I had two excel sheets
in one workbook that I was able to union together.
Then I pivoted Col1 and Col2 into one column.
I got the max value using WINDOW_MAX(MAX([Pivot Field Values]))
with a Compute using of Pivot Field Names and Table Name, restarting every Pivot Field Names.
Then colored according whether equal to that max value:
MAX([Pivot Field Values])=[MaxValue]