You really tried your best to break my game haha.
In your video, at 7:31, I can't believe you've been there so many times yet still didn't see that chest, Vermis' words weren't aimless when she advised you to check the office.
As for the bridge, It doesn't re-spawn endlessly, you should've been more careful the third time, but even with the bridge destroyed there's still another ending, but for that one you needed to open the chest at 7:31. I even added a brighter light behind those stairs to make it stand out, but it seems it's still hard to notice, I may add a Vermis comment there in the next update.
Anyway, thank you very much for playing and sorry for the inconveniences, that loud oscillating sound as well, I will delete it in the next update( but I think you know you weren't supposed to go there, I will block entry to that room completely).