This may or may not be a bug, but this makes the quest battle impossible. In the very first battle Stunky runs out of Sucker Punch and switches out, then returns after Frillish is defeated and uses Struggle. The guide suggests that Stunky should be debuffed, but it shakes off the debuff with its switch and then beats what's left of my pokemon with one Struggle. If this is an intentional change to the quest, it seems too hard for the first battle.