It was a sad news for me that Fushigidane left the cast since he was needed to calm down the group of Pokémon at Okido's laboratory. I think it is simply just a reason for Satoshi to store his Fushigidane in order to give room for Johto Pokémon. Generally this episode was awesome and nice to see that Fushigidane can actually be the one to stop the fighting.