The Making of the South Park WoW Episode
Yes, since I now know what it was saying I can see why it's acceptable, but it wasn't immediately clear to me (not being someone who plays WoW or watches South Park regularly). I red it as South Park was being used an adjective to describe a WoW Episode.
"the red dog's collar" may mean "the collar belonging to the red dog", or "the collar (which is red) belonging to the dog".
So "the dog's red collar" is more clear.
How about "The Making of the WoW Episode of South Park". That's much less ambiguous. :-P