For your situation and group size this might be best though early traditional may be full by now.
BTW, MT booking should work but others have reported issues with availability.
That may not be Royal UP related, especially this far out. Having insides disappear likely have nothing to do with Royal Up as people move up from those so if anything, inventory should go up on those not down. Royal does inventory management all the time when inventory disappears like that and then they come back after a few days.
Depends on how reliable you expect it to be - it's pretty good but not anywhere as reliable as land-based internet. For most people most of the time for most function it is usable to work on the ship.
It should be quite obvious if you were charged or not when you first bought the package - if you were never charged, not sure there's much you can do about it as you never bought it (regardless of why it didn't go through). If you were charged and then got a refund, that's different and in some cases the remedy is to ask for OBC for the diff between what you originally paid and the current price (and buy it at the current price) - RCI has allowed that in some cases. It's still not obvious what happened here.
@Ourusualbeach may be able to confirm if the planner items, including excursions, are available to TAs. If so, you'd have to contact one who would be willing to pass the info to you.
You may also see if someone in the Roll Call thread for that sailing may provide that info.
The cabin stewards may be quite good at getting stuff, but they can't get you something that is not on the ship - not sure there are any on board even if they wanted to swap them for you.
You could have asked here on CC and would have been told that interporting sailings like yours have issues as you describe, and planner and other items may never become available. RCI giving bad info is fairly routine.
No, but what is available on board which is not available in the planner is a 24 hour plan - you know, for that sea day when you can't live without access.