Crap, i'm sorry for missing this VM.
Truth be told, it doesn't really look like a strong set. Volt Switch is pitifully weak on something with "so-so" SpA and no STAB. Cobalion already has an onsite set that uses Close Combat / Stone Edge and HP Ice, so I don't think making a set solely based on Choice Scarf will work. Cobalion shouldn't be revenging Volcorona either, we have Terrakion for that, etc.