This party is held ot the "grassy knoll" at the International Gateway to Epcot. They put up a big tent and it is even air conditioned!
It isn't held at AKV, but going by the name it will have a AKV theme in order to be in line with the current sales initative.
If your kids like to dance and see characters (I just remembered characters were there) I would schedule an Epcot visit for the Thursday afternoon of your vacation.