We also had a lot of issues with the dungeon. In the Victini Dungeon in almost every run we had if we kill Kyurem white and black at the same time one of the barriers (most of the time the Kyurem black barrier) didnt dissapear. Also Kyurem respawned always at the bottom of the room with full health. We also had the issue that we had to defeat Victini 4 times to exit the dungeon (the player who defeated the third victini could leave the dungeon, but Victini respawned for all other players).