Having read the OP's complaint a couple times, it seems like ( to me--just my opinion ) that they basically left everything up to the Princess agent.
If I wanted a balcony and was told it was put in someone else's name I would immediately tell them there was a mistake and it would either be corrected then and there or I would call off the deal, make sure I had all my ducks in a row and call another agent and go over everything in detail to be sure it was correct. I wonder too if this was a last minute booking and as they left everything up to the Princess agent, they could only do so much regarding dining times, cabins,etc. I don't get the part about a temporary key--who paid for the balcony, etc. That in itself could create a problem, as the person booked into the cabin would be responsible, most generally, for the on-board account, etc. regarding that cabin and would require quite a bit of work on the purser to get that straightened out when all they have is what is sent to them from the home office as to which person is in what cabin, etc. Regarding luggage, if the wrong luggage was delivered to the wrong cabin and the right cabin was within a reasonable distance, and especially belonged to someone in the group, I would have simply changed it myself in a matter of 2 minutes or so and avoided any complaint to the steward, who seemed to be as confused as the OP as to who was on first.
Also, it appears that they probably booked guarantees, or at least some of the group did and may have been " upgraded " to a cabin that had an obstructed view. People should take a lesson--moving up a deck or 2 doesn't always mean you're getting an upgrade but there's always that human emotion that to some, if they hear that word " upgrade " they automatically think they're getting a better deal than they paid for. Some folks think that if you get to move up a deck, you get a better cabin-you could,and many times do, end up being "upgraded" to something you wish you didn't have.
Seems like there wasn't a lot of thought or pre-planning that went into this cruise. Just to call up and book a cruise without being specific in what you want and expect , such as cabin, meal times,any special occasions, etc. sometimes doesn't pan out the way you want it to.
When I book a cruise, I use a T.A.and I know before I call the deck and the cabin I want, the dining times, the type table ( large or a table for 2 ) etc. and then when I call, I go over everything in detail, then when we get it finalized, I re-cap again just to be sure we're on the same page and when I get my confirmation, I carefully go over it to be sure all's well. So far, I've never had a problem.
Bottom line, do some homework, look at the layout of the ship, understand what a guarantee is vs. booking a specific cabin, understand the dining times and etc.and then when you do call, you have at least some info to depart to the booking agent as to exactly what you're looking for.
Just my opinion that means nothing to anyone but me !