Need help with DAX

Hi All,
Firstly sergej_og thank you for your solution!
And Anonymous ,I tried to replicate your data for testing, when using is_member for testing, it is possible to filter according to the filter, it is possible that my data is too simple to replicate your specific problem, we also tried other DAX to realize your needs, you can try to see if it can accomplish your needs!

CountPresentOrgsFiltered = 
CALCULATE(
    COUNTROWS('participants'),
    FILTER(
        'participants',
        NOT(
            ISBLANK(
                RELATED('all_orgs'[ORG_ID])
            )
        )
    )
)

CountPresentOrgsFiltered2 = 
CALCULATE(
    COUNTROWS('participants'),
    TREATAS(
        VALUES(all_orgs[ORG_ID]),
        'participants'[ORG_ID]
    )
)

I hope my thoughts are helpful, and I would be honored if my approach solves your problem!

Hope it helps!

Best regards,
Community Support Team_ Tom Shen

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