The game's name is
"Finny the Fish & the Seven Waters"
So Redon's hint has something to do with Fishmen or Water Seven
Water seven...Maybe Lucci and the Marines show up with a buster call
Maybe the Fishmen pirates arrive from WCI and we finally find out what happened to them and Germa
Or maybe Zou finally shows up and attacks the flying island
Or maybe Redon is just recommending a vintage PS2 game and we're all reading way too much into it