[GAMEPLAY] Face of the Mountain Passive not activating properly.

My friend and i were playing as Gangplank and Wukong both with Face of the Mountain. While trying to apply the Face of the Mountain passive (Gold given to team-mate), Gangplank with lower Q (Parrrley) damage than Wukongs Q (Crushing Blow). Gangplank would apply the passive on minions of same HP that Wukong could not.

In short - A Gangplanks weaker Q would apply the passive where Wukongs stronger Q would NOT apply the passive.

Also: The Execute damage in the description of Face of the Mountain was listed as being "603" for me (Wukong), though even on minions with less than 603 HP, it would not apply the passive with either his Q (Crushing Blow) or Basic Attacks.

On the League of Legends Wiki, it describes the Face of the Mountain as having a flat amount of Execute damage: "UNIQUE – SPOILS OF WAR: Melee basic attacks execute minions below 400 Health.". I'm not sure if the Wiki is correct with that information, but it would make much more sense than the actual item description.