Count Measure

Hi ArchStanton 

I am assuming the bold rows are the primary topics:

Create a new measure:
Count Secondary = 
IF(
    isinscope('Cases'[SecondaryTopic]) --Returns true for Admin but false for Auto enrolement

    ,DISTINCTCOUNT('Cases'[SecondaryTopic])

)

For the primary its a little harder as IsInscope would return TRUE on the row of Auto and Admin since Admin is nested into Auto.

Count Secondary = 
IF(
    Not(isinscope('Cases'[SecondaryTopic])) && isinscope('Cases'[PrimaryTopic2])  

--Must return FALSE on Admin  AND return TRUE on Auto (excludes row and grand total)

    ,DISTINCTCOUNT('Cases'[PrimaryTopic2])

)