Koops Rejection Softlock

[Demaar]

So, I decided to tell Koops he can't come with me to fight Hooktail because I wanted to see how far you can get without him.
The answer is, Past the Sun/Moon Stones but not into the Castle.

Anyways, When I noticed the Castle area transition wasn't loaded, I went back to get Koops but, he wasn't there. Instead, the Cutscene with Koopie Koo played. Specifically, the version from the Vanilla game.

So, No Koopie Koo battle, No Koops anywhere and No way into Hooktail's Castle.
Just Lucky I didn't save over my Savefile.