Hi Sarah,
If I'm understanding correctly, what might help would be to make sure you include entityuri as one of the attributes in your Organization.ClientOrganization reference attribute definition. With that done, your filter could look like this:
filter(equals(type,'configuration/entityTypes/Organization') AND containsWordStartingWith(attributes.name,'App') AND equals(attributes.ClientOrganization.entityuri,'abc123'))
Please let me know if this helps.
Kind regards,
Matt
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Matthew Gagan
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