I read on Spider Web and Mean Look on Bulbapedia and they said that if you switch with Baton Pass, the opponent won't be trapped. In other words, SW and ML can't be Baton Passed anymore.
I'd change the set for something like this:
-Shell Break/Curse
-Spore
-Recycle
-Baton Pass
Nature: Jolly
EVs: 252 HP/4 Def/252 Spe
Item: White Herb
Ability: Own Tempo
No need for Curse+White Herb when you can learn Bulk Up.