1 Gem missing to a 100%. According to hud skull it's in this room.

https://preview.redd.it/rtceuc7hbv4h1.jpg?width=1920&format=pjpg&auto=webp&s=ce1c2824e99eb635b753667abf836bf37959d700

The only thing in this room is this chest i destroyed within first few hours of gameplay. I wanted to get 100% before starting ng+ and according to hud this is the room with the missing Gem. Is there something else here or did it somehow bug and not count?