You have 9 people going, are you all staying in one room?
If there are two rooms you could consider buying the
DDP for just one of the rooms and sharing credits. Use the credits just for the buffets and more expensive QS, OOP for everything else.
If you are all in one room, and would then have to buy it for everyone, it's probably better to skip it. It will most likely not save you any money (maybe cost you more), but also it will rule over your group. A group that size will do better without confinements.