You can delete only an entire specific broadcast routing, not individual destinations within it. When you delete the normal record for the first destination on a specific broadcast routing, all the records for the other destinations are deleted with it.

To delete a specific broadcast routing, follow the steps for deleting a normal routing file record. See Deleting records from the routing file. If this is a routing with multiple destinations, the records for all the additional destinations will be deleted along with the first one.