*throwsn in my two cent* I dont know the big plan.

 But. If I were  in the pokemon club doing legal trading and Seth walked up to me to say what he did. I would smile say of course we will get your pokemon back. Show me your pokedexs so we know which ball with a vulpix is registered to you.

Oh you have ZERO pokemon to your name. Call the police for attempted theft!

Oh she doesnt have a pokeball? She is a wild pokemon then and doesnt belong to anyone. And whoever catches her with a pokeball  first is her trainer. You failed to catch her you have no legal ground to demand her. 

*shrughs* But alas, I have zero idea about the big plan.