Hi Felix,
You can do it either of 2 ways
1. Using Recipient as Filtering Dimension and using 'Don't exists such as' query on broadlogRcp. Below screenshot
2.Starting BroadlogRcp as filtering dimension and than changing dimension back to recipient.
I prefer option 2 as option 1 is sub query execution and sub queries are know for there performance hit.
Let me know if you need more details on any of these options.
Regards,
Ankur A.