I mean, the Persona manga series (3, 4, and 5) are all over 10 volumes. It wouldn't surprise me if that was the case here as well (Metaphor is currently in volume 2)
I think this manga would have benefited from a volume 5, like the Days' manga. A couple extra chapters of Disney worlds to complete volume 4 and then an entire volume dedicated to the end of the game. If that was the case, volume 5 would have more space to better deliver the story, without it...
It's great to see some of Yen Press' lost media chapters coming to light! I remember that they had released up until Arendelle or something like that; do you happen to have any more of those chapters, or is this the last one avaliable?