Cross Slicing - using DAX to change the filter

[belvoir99]

I have some survey data example. There are 4 respondents who have answered two questions: Bundle and Provider (short hand for each question). Provider is a single answer type question (e.g. radio button) whereas Bundle is a multi-answer type question (e.g. checkboxes). Their answers are shown in the form of "Q8A1" etc but obviously in the real world problem they would be more meaningful.

I want to cross slice by clicking on the top left table's Q8A1 column. There are 3 respondents for this. On the cross slice to the Bundle visual (top right) I want to count only those responses from those 3 respondents - returning 1 for Q10A1, 4 for Q10A4 and nothing for Q10A3.
This is the data table:

RespQuestionAnswer

R1	Bundle	Q10A3
R2	Bundle	Q10A1
R3	Bundle	Q10A3
R4	Bundle	Q10A3
R1	Bundle	Q10A4
R2	Bundle	Q10A4
R3	Bundle	Q10A4
R4	Bundle	Q10A4
R1	Provider	Q8A1
R2	Provider	Q8A1
R3	Provider	Q8A2
R4	Provider	Q8A1

Here is the OneDrive link to the PBIX file: Survey PBIX file 

The DAX measures in the PBIX file - please ignore my hopeless attempts to solve this problem!

Any help gratefully received! Thanks so much.

[belvoir99 · Accepted solution]

I'm closing this as unresolvable. 

It's clear to me that, when a cross-filter is passed to another bar chart visual , you cannot add to, amend or remove that filter. It is one area in which we don't have control over the filter context.

Back to the client to discuss alternatives!

[belvoir99]

Just as an additional thought:

although when you cross slice it passes a filter in the form of 

  VAR __DS0FilterTable = 
    TREATAS({"Q8A1"}, 'RespondentAnswers2'[Answer])

It seems to apply this filter after any CALCULATE statement, e.g. any measure acting on the receiving visual will, in DAX Studio, return a syntax such as (stripped down):

DEFINE
  VAR __DS0FilterTable = 
    TREATAS({"Q8A1"}, 'RespondentAnswers2'[Answer])

  VAR __DS0Core = 
    SUMMARIZECOLUMNS(
      'RespondentAnswers2'[Answer],
      __DS0FilterTable,
      "MyMeasure", 
      COUNTROWS(
		    CALCULATETABLE( 
		        RespondentAnswers2,
		        REMOVEFILTERS(RespondentAnswers2[Answer])
	       )
       )
    )

EVALUATE
  __DS0Core

The calculation returns:

which seems to indicate the TREATAS cross slicer is applied after the CALCULATE statement... in which case I need to restructure the table and not try to find a solution through DAX.

Another way to think about it is to say that the __DS0FilterTable is in effect filtering the  'RespondentAnswers2'[Answer] table before applying the measure (to deliver the X axis) and I can't influence that...?

At https://dax.guide/summarizecolumns/ SQLBI explain the FilterTable as:

An expression that defines the table from which rows are to be returned.

I would be very happy if someone has a solution - including changing the shape of the table, breaking it up into a star schema, etc etc