I would write to them in Miami. If you add a VP name at the address, pick one of the top guys, it might get more attention.
I can tell you what you experienced is not so rare. Last Sept we sailed right into Tropical Storm Nicole and the captain tried and tried to dock, but could not make any head way into this storm.
The reason they were so determined to dock, was our entertainers were there waiting to be picked up. This storm was so bad the day in port would have been ruined, with tropical downpours and mud slides.
Because of sailing right into the storm .. now we had to sail back thru the storm to get home .. or our next port, which was the Caymans which we also missed.
The contract says if you miss a port you will get the TAXES on the port fees back is all (nothing close to the port charges). You had to agree to this to print out your boarding pass.
Did Carnival substitute a port for you or just you missed a port? I notice you mentioned going to another port, in which case you are owed nothing per the contract.
I can see why you would be dissapointed. I suspect this happens more than people know. I too was told that the ships never sail into a storm .. so what did we do .. sailed right into the storm. We had some kind of the front end of the ship going up up up and then dropping for about 24 hours.. so some people got sick on our cruise as well.
I was also on Conquest when Ike wiped out Galveston and we were dropped off in a completely different city than we left from .. now that was a big problem .. missing a port, not so much.
I do get that you feel the actions of the captain caused some of your friends to be seasick and I am sorry they had that happen. .. how much compensation are you seeking? Maybe some here can tell you if that is even something that might happen if you write?