I don't know if anyone found this before, but seeing an archived halfchan thread suggested no one had. The original has been deleted from Youtube for some reason. It took me 30 minutes to find, which is still 30 minutes too many for such a benign video. So screw you Youtube faggots.
>https://files.catbox.moe/n22txz.tar
I can't post the video for some reason and when I tried to upload just the video to catbox it was only audio. So I .tar'd it in the hopes it makes the video watchable for you. Let me know if it's not.
Frankly it sounds a lot more like people being murdered or tortured or pranking in the tunnel than a ghost, but you make up your mind.