The tender tickets on the Conquest are just for crowd control. They use them early in the morning to insure that those on early excursions can get off the ship on time. You go to the lougne, tell them you have an excursion at x AM and they will give you a ticket for a tender before then. They don't care if it is not booked through them. They just want to avoid a bunch of people wanting to go ashore to walk around and shop from preventing those on a schedule from getting on shore. Once the initial rush in the morning is over, the tendering process goes pretty much ticketless. The only time I saw a problem was on our Victory cruise that follow Huricane Emily across the Caribiean. Because of the huricane causing last minute port changes there were 5 huge cruise ships in Grand Caymen at once which really taxed the GC water taxi services. Many people missed out on their excursions in the morning. Luckily we had heard about it and left for shore hours before our scheduled time.
Carnival Cruise Lines:
Fantasy 90, Celebration 95, Victory 05, Conquest 05, Spirit 6/06, Freedom 6/08, Holiday 7/08, Victory 6/09, Valor 9/09, Dream 6/10, Splendor 8/10,Conquest 8/11,Magic 11/11,Triumph 4/12,Spirit 7/12,Freedom 11/12, Triumph 2/13 - The fire cruise
NCL Dream October 2006, RCCL Mariner OTS June 2007, Celebrity Silhouette 2013