added a screenshot maybe this makes it clearer: sorry feel free to delete the comments here did not know what the right channel to share this info is ^^

https://steamproxy.net/sharedfiles/filedetails/?id=2577255018

To be more precise: I think it works with any of the glass walls if you have sufficient speed. No idea how collision works in this game but I guess because the glass walls are so think the game misses a check. However the glass wall at the end of the tunnel is the easiest to pull off because you face it head on anyways and usually have high speed.

Hello, just read your DK guide. There is an easier and more reliable OOB on red planet medium and long: In the last tunnel in the sharp right turn just aim for the border between glass and pillar. Hope this helps with speedrunning