Yea, the same thing happens for the Celestial Griffon, which has the skill: 

"Death Gust (Cooldown: 3 turns) Removes all buffs from all enemies, then attacks all enemies. The buff removal cannot be resisted. Damage increases by 10% for each buff removed."

Brogni's shields are not removed in this case either.

It seems that when an irresistible force meets an immovable object, that the immovable object actually wins.  The age old debate is now settled!