OP, it is your decision and I respect that. Any of us will offer our opinions, but they are just that and only you can decide what is best for your family.
Just a couple of thoughts on some items posted about this, and agian this is just my opinion which does not make me right or the expert but:
I do not agree with the post saying the whole family needs to pull together and take the punishment and help the 11 yea rold. That is not DD 14's job to do.
As someone with 4 siblings and one who constantly pulled things - and still does even as an adult with their own children - that ruined events and outings for all of us, yes, your other children will remember and very likely resent DD 11 for this.
In some ways, in addition to "punishing" DD, you are also empowering her tremendously. This 11 year old now will realize that by her actions she can change decisons and plans for the entire family. You are giving her power and control, and possibly, next time there is a family event she does not want to go to, she will act up so it too can be canceled for everyone.
Personally, I would find a punishment that affects only her and not everyone.
Again, not a judgement, just my opinion and only you can decide what is best for your family.