Oh I mean the message about the caverns shifting and you returning to the surface forgetting your memory. It happened shortly after I went out of bounds, and was put to the last checkpoint, I was then given the message I think
Oh no! that is a bug, there's 2 endings and the one you got is from descending to the final area, then riding the lift back up to the top, I just realized the check point for that part is in a spot that lets this happen!! You met the condition of going to the bottom (when you jumped out of bounds (likely dying as you hit the trigger)) and avoided the next checkpoint! tldr, thank you for making me aware of this, and you unintentionally triggered the secret ending lol