The jamcruise should have put a system in place after the people got left in bahamas on JC1. At least JC2 people were in the U.S., so it could have been worst.
I'd like to add something without taking sides on this..... ships do not have the luxury of waiting on people. Docks are run much the same way as airports; one ship leaves and another docks. There is no time to wait indefinitely for passengers who don't show up on time. Think about it; a boat is docked in Jamaica and 2 passengers don't show because they were arrested for some reason. If the ship waits, they will be waiting for a very loooong time. This kind of stuff happens and the people on the dock have no way of knowing why someone doesn't show. Meanwhile, there is another ship waiting to dock and other passengers to consider.
It is not uncommon for people on cruises to be left at port of call. In fact, it happens all the time. I'd also be willing to bet money that they have this covered in the fine print on the ticket contract.
Like I said, I'm not taking sides. Just pontificating.....