Unable to bring a marked Duplicate Person into an Ongoing Case

Once a duplicate person has been added to an ongoing case, it is impossible to bring the Master record (person) into the case without ending the duplicate as a member including end dating the removal record etc.

Issue mentioned in the customer case:
"You are able to initiate the Ongoing Case without selecting/bringing in the marked duplicate - if the duplicate was not the primary client. You can then add the Master/correct person to the Ongoing Case.
When you attempt to omit/not bring into the Ongoing Case the marked duplicate, who was the primary, you receive an error message that the primary client needed to be added to the case. You are able to change the primary client to the child and could then initiate the Ongoing Case.
When you attempt to initiate the Ongoing Case, bringing in a marked duplicate, you get an error message that the person could not be brought into the case because they were a duplicate. Once unmarked the caller brought them into the case - for testing purposes. With the marked duplicate he could not enter a contact log, do a visitation plan or enter a relationship (could if not marked) but could save a legal status. He could not delete the duplicate if they were the primary client but could end date them. The end reason noted they were a duplicate.
When the duplicate was not the primary client they could be deleted from the Ongoing Case and the master person could be brought in"