It normally goes that the quacks have a shot first if you send them there.
After that its a practical test by a person who is defined in your OPS manual who then submits some paper work to the medics in the NAA.
In some ways I can see why CC may have issues where as Pilots don't because the Pilots can control the volumes getting put into there headsets.
The only thing you can do is ask your NAA medical branch. Don't ask the flight safety etc because they won't have a clue.