2 episodes of 10 minutes in one? That never happened in Pokemon's Anime. I don't understand why they didn't make these two as episode of 20 minutes, but I was expecting an episode about Magikarp from some time. (A Magikarp appeared in the promo poster of this anime). I don't know where will Goh capture it, but it calls my attention they say his Magikarp is quite "fat". I suppose it will evolve to a bigger Gyarados than usual, giving Go another Powerhouse like Golurk.
Anyway, I don't see a Slowking as a suitable Pokemon for Ash, except for the Slowking that guided Ash in the second movie (the one with Lugia and the Legendary Birds). Similar to how Ash bonded with the Lucario from the other movie and we wanted him to catch one. Problem is, however, Ash already has too many Water Types, if you ask me.