Hide certain row headers

Thanks for the response, not quite what I was after but very useful.

I have managed to self solve so adding my solution in case its helpful to anyone going forward.

Blanked out all the actual metrics here but when a primary_resource is selected in the slicer, the table matrix remains unchanged other than the unselected primary resources are now blank. This allows this to be used as a "league table" while keeping the unselected names confidential.

This has been acheived by hiding the row headers entirely and using a measure to create row headers instead. Measure as follows

Selected_Primary_Resource = 
VAR FilterName = IF(
    HASONEVALUE(Provisioner[Primary_Resource]),
    VALUES(Provisioner[Primary_Resource]),
    BLANK()
)
RETURN
IF(
    HASONEVALUE(OT_Temp[Primary_Resource]),
    IF(
        ISBLANK(FilterName),
        VALUES(OT_Temp[Primary_Resource]),
        IF(
            VALUES(OT_Temp[Primary_Resource]) = FilterName,
            VALUES(OT_Temp[Primary_Resource]),
            BLANK()
        )
    ),
    BLANK()
)

The provisioner table is an unlinked table so when a single provisioner is selected, only their name appears and the others are blank.

Sorry if the explanation is rubbish. Hope this helps someone in future. Would be great if powerbi could add conditional formatting options to row headers so this would be much simpler to achieve.