Crystal Chronicles help

[amplas]

I've searched every room in moschet manor but I can't find any way to progress. Please help.

[Water ☮]

you must kill all the tonberry chefs!!!

[amplas]

you must kill all the tonberry chefs!!!

That's what I thought at first, but then what? Last time when I killed all of them, nothing special happened.

[Kaz]

you must kill all the tonberry chefs!!!

That's what I thought at first, but then what? Last time when I killed all of them, nothing special happened.

If you actually do kill them all, then all you have to do afterward is go out into the main court of the manor. You know, where you start out. Then the boss fight should start.