You seem to be the man in the know, so I'mma ask you.
Party hat (pink and purple stripes)*
Short rainbow hair*
Colorful Suit Outfit (CP28) - Plunger hat guy
King Outfit (CP185)
These are the items I've yet to collect, but according to your guide, those with a * besides them we start with, or are given once we've finished the story/collected everything in the story.
Well, I've collected everything in the story, yet I don't have these items. Is it possible they've disappeared, which I think is the case with CP28, unless I'm either too stupid to know what it looks like, or I've misinterpreted the guide incorrectly.