SSRS Interactive Sort Row Group data from a column group

In SSRS, I am trying to do interactive sorting in a combination of a group of columns and a group of rows.

So my data will look like this:

    -------- ------------- --------- -------- -----------------
    Category  CampaignType  Campaign  Quarter Value   
    -------- ------------- --------- -------- -----------------
    Cat 1     CampType1     Camp1     Q1      1
    Cat 1     CampType1     Camp1     Q2      4
    Cat 1     CampType1     Camp2     Q1      51 
    Cat 1     CampType2     Camp1     Q1      3 
    Cat 1     CampType2     Camp1     Q2      1  
    Cat 1     CampType2     Camp2     Q1      3 
    Cat 1     CampType2     Camp2     Q3      56 
    Cat 2     CampType1     Camp1     Q1      8 
    Cat 2     CampType1     Camp1     Q3      11 
    Cat 2     CampType1     Camp2     Q1      2
    Cat 2     CampType2     Camp1     Q1      23 
    Cat 2     CampType2     Camp2     Q1      3 
    Cat 2     CampType3     Camp2     Q2      8 
    -------- ------------- --------- -------- -----------------

So, I am grouping the lines:

-Category
 --- CampType
 ------ Campaign

Group by column by row.

Getting the sum "Value" at the intersection of these two points.

Add some summary and we are done.

I would like to be able to sort the campaign cost per quarter.

This, in my opinion, seems like a reasonable request.

First, see how it looks in the designer, and then an example: