The dive operator "runs" the trip. The club is merely coordinating some divers. So we say "join us on April XX where we will dive the blah-blah wreck. the wreck lies in 97 feet and is considered an advanced dive. AOW and a wreck specialty is required for this trip. Contact XXXX Dive Boat to reserve your spot now!"
the club is not an entity. Sure, a diver with a problem could sue the operator, can't sue the club, can't sue the board (there isn't one), could sue individual members (but it would be very hard to show any kind of responsibility on their part).