Ajani controls
AEther Vial, which has 2 charge counters on it, and its activated ability is activated. With the ability on the stack, Nissa casts
Ancient Grudge targeting the Vial. When the Vial activation resolves, per 112.7a, the game uses the last known information of the Vial to allow Ajani to put a creature with a CMC of
2 onto the battlefield, correct? Hoping to clear up a dispute with a friend.