In the past, I never booked through a cruise ship. For a few stupid reasons due to my poor judgement recently, I did and will never do so again. This is what I basically found out the hard way: I broke this down into sections so they can be analyzed.
1) The dive shop never asked anyone for proof of certification.
. . . stuff deleted . . . .
9) Two of us team up to release the boat from the mooring and allow the captain to reposition to pick up the 2 divers who are waiting with the DM clinging to another mooring ball. After a few throws, we connect and haul in the 2 exhausted divers. At this point the captain says we are done for the day. The DM lets us know that we will only be charged for a single tank dive. Really?
This has little to do with the ship, which actually has almost nothing to do with the dive except for taking a cut of the money. It's entirely dependant on the dive operator.
I've done a lot of cruise ship dives and while many were pretty cool from a "keeping your rescue skills sharp" point-of-view,, others were actually quite nice. Hugh Parkey in Belieze did about the best job with this.
As for your specific experience, you have to dive your own dive. Nobody can
make you do anything.
Just to address your points, here are a few thoughts:
1 & 2: Nobody is required to check anything. Your SCUBA C-Card is simply a piece of plastic issued by a private company that says they trained you. The dive OP isn't required to ask for or see this, any more than they're required to see your AAA card.
3: Assuming you had normal recreational Open Water training, you were taught how to dive safely with a buddy. This means "your personal buddy." A 1:1 relationship. Unless you hired him to be your buddy, the DM isn't it. He is leading the group around, and as you found out, doesn't have your personal safety at the top of his list. He has another 8 people to keep an eye on.
4: I have a bunch of dives, but when someone who dives the same spot probably 4 times a day for years thinks the current is "stronger then usual", there's a really good chance that I'll tell him to enjoy the dive, and I'll go work on my tan.
5: Unless you can ascend to the surface from the inside, you were in an "overhead environment" if you had someone in front of you and in behind you, and you panicked or ran out of air, you would have been in a world of brown stuff. I never go anywhere on a single tank recreational dive, where a complete stranger can trap me in what is essentially a cave.
5b -7: Any time you're in a dive that isn't going well, feel free to return to the boat. There's no reason to be going up and down and hiding from the current and losing people on a recreational dive. You should always know where the boat is, and end the dive whenever you're feeling uncomfortable with the way things are going. If you want to be nice, get the DM's attention, point to you and your buddy, make the "boat" symbol, show him your thumb and wave goodbye. If you can't easily get the DM's attention, leave anyway. He'll be just fine, and once you get back to the boat, you'll be fine too.
8: Your stuff is your stuff. You're responsible for it. Nobody is responsible for taking it from you on the way up the ladder. Also, you should have been taught how to re-board a boat without handing anybody your fins (which BTW is a bad idea from a safety standpoint).
The only real problem here was that this wasn't your dive. You were doing what people told you to do, not what was right, or what you were (or should have been) trained to do.
flots.