I have yet to see the episode in motion, but I'm glad the power plant from the games was at least included, even if they didn't include the whole Galactic arc that occurs there.
Yeah, I am disappointed, another episode of D/P that could have been great and wasn't. It was so easy to make a plot, the girls say to Ash and Co. that they have little friends in a cave, the frieds turn out to be Fuwanteds that are luring them, and then they have to rescue them before they end up in the underworld. So dark, they could have also included a family story, the grandfather made a deal with the fuwante, they would take his grandchildren in exchange of money. Geez, such a great story was missed.
In a KIDS' show? Look, the underworld thing in the Pokedex makes for some admittedly funny gags, but nobody should seriously expect them to include it in this anime. It's times like this I'm glad the fanbase isn't writing this show.