Mary, Since you are going to open this can of worms. Here goes.
Neither should have any claim to the Nickname!

Why, because in a sport as small as ours, it only confuses those outside the sport of catamaran racing.
This type of stuff is one reason why we are and will always remain the redheaded step child of sailing, we can't even agree on who get's the nickname.
Both set's of organizers need to set thier respective ego's aside and just run with the name's they have chosen.
If the racing on either side is good, over time, no one is going to care what the nickname is or was.

Good Luck to both groups, what ever name you chose to use.

CO