Filter table based on multiple columns from different tables

[arnomics]

Hello community,

I have a tricky situation & since I'm still learning and understanding DAX this has been a tough cookie to crack. 

To make things difficult I'm using a published dataset which restricts my ability to do custom columns etc.

The problem I have is based on the Data Model image below. 

I am trying to create a Measure that gives me a count for each Phone based on the below:

1. [Flag] from Contract Table = "YES"
2.  [Publication Channel] from Fulfilment Table = "Digital" or "Print" 
3. Most importantly, I only want to identify [Phone Number] from Phone Table where [Account Code] from Service Table = "HCODE"

The issue is that I  have a lot of Rows for [Phone Number] which makes it difficult. However, I've checked this, I only have around 2000 unique Phone numbers that match my 3rd requirement ( [Account Code] from Service Table = "HCODE"). So, essentially, I want to isolate these 2000 distinct Phone numbers to use with other Measures.

Below is what I've come up with:

Count =
VAR phonefilter =
    FILTER ( 'Phone', 'Phone'[Phone Number] = "9852070618" )
VAR PubChannFilter =
    CALCULATETABLE (
        VALUES ( 'Fulfilment'[Publication Channel] ),
        'Fulfilment'[Publication Channel] IN { "Digital", "Print" }
    )
VAR CombinedTable =
    SUMMARIZECOLUMNS (
        'Phone'[Phone Number],
        'Fulfilment'[Publication Channel],
        phonefilter,
        PubChannFilter
    )
RETURN
    COUNTROWS ( CombinedTable )

This works fine as I only am looking for a single [Phone Number] = "9852070618"

How can I create a list of only the 2000 unique Phone numbers that match my 3rd requirement ( [Account Code] from Service Table = "HCODE") so that I can use with VAR phonefilter  instead of a single phone number.

I'm trying to do this so that I can have the Measure optimized.

The output on a Table Visual should look something like below:

Phone	Phone Publication Channel	Flag	Count
9852070618	PRINT	Yes	1
9852070618	DIGITAL	Yes	1

Hopefully someone can help me out. or Provide feedback on my existing DAX/variables.

Thanks.

Data Model