I've been contacted by a passenger on the cruise before ours. They also had dreadful treatment from Costa but were offered no compensation whatsoever. I'm asking permission to repeat what this passenger has told me and will post it here if he agrees.
I've also e-mailed the main coordinator of the passenger protests on this previous cruise in the hope that maybe it will work to the advantage of us all if we combine our efforts. There are a number of things that we can do to fight back against Costa's apparent institutional failure to respond appropriately to customer complaints. For example, take a look at this example of an ordinary consumer fighting back and landing some very heavy blows.
Watch this space.