DAX Conditional Formatting the maximum value for each column in a Matrix

Hi, I followed this post and video but cannot figure out a few things, hoping someone can help me figure it out. 

https://www.sqlbi.com/articles/highlighting-the-minimum-and-maximum-values-in-a-power-bi-matrix/

Essentially, I want to do what they highlight here, but for the GP column for each of these (Cloud / Network / Security) in my image from my matrix visual.

All of the data is in a single table 'SAP-DIRECT', and the rows are [EAM] and Columns are [GROUP]

I am trying to show a Star Icon for largest GP, and would be a bonus to show another icon for the 2nd largest GP but not totally needed.

My current measure is below, I use that for conditional formatting - Values Only - based on the measure, if = 1 etc. 

One thing I have never seen explained when people show this method, what is the [Sales Amount] Measure that is called in the link above?  

I created one called [GPmeasure] and just use Sum for my GP value, but have no idea if that is right. 

Currently this is what shows in the visual, no icon on any value. 

My current measure: 

GP LARGEST SAP-DIRECT =
VAR Vals =
CALCULATETABLE(
ADDCOLUMNS (
SUMMARIZE ( 'SAP-DIRECT', 'SAP-DIRECT'[EAM], 'SAP-DIRECT'[GROUP] ),  -- I believe I have this correct? Row first then Column?
"@GPMAX", [GPmeasure]  -- This is my measure I created, see below, not sure if it is correct? 
),
ALLSELECTED ()
)
VAR MinValue = MINX ( Vals, [@GPMAX] )
VAR MaxValue = MAXX ( Vals, [@GPMAX] )
VAR CurrentValue = [GPmeasure]
VAR Result =
SWITCH (
TRUE,
CurrentValue = MinValue, 1, -- 1 for MIN
CurrentValue = MaxValue, 2 -- 2 for MAX
)
RETURN
Result

My measure that is called by the above: 

GPmeasure = CALCULATE(SUM('SAP-DIRECT'[GP]))

again have no idea if this is right, or needs to be SUMX? 

My Conditional formatting - fairly certain this is correct

Thank you so much for any help!