Here we have a filler arc for those who survived the war when Siwa fell and everyone not taking it in a good manner, especially the lugias who want Kroko to suffer. Many key figures are in this arc, but it's mostly a side arc like what one piece or boruto does. Or how cartoons stray away from the main character to give some side characters the spotlight. It's pretty short since this was just a small side story about how everyone took the news, like the end of Marineford Arc or the side stories from PMD: EoS
Veronica and Eclipse are future characters that'll come into play at some point, but the ones who may never forgive kroko no matter what is Veronica and Mako, Yuri's not a pamp god anymore so he can choose weather or not to forgive him. The Kyogre is no future character, he's just a Lugia guardian and doesn't take kindly to pirates and invaders since he's guarded Veronica and her kind since she was just a hatchling

Part 3 comes Arthur's downfall and ascension to a pamp god.

Characters belong to their owners, too lazy to type everything out.