O_O Imho, this is very realistic and there is no way it could have been faked. It must be some extension to PD72 that MT was originally planning to release, but they changed their mind and didn't bother to remove it ... The title is "Unknown Dimension" and the description says "The prohibition of teleportation at the end of a dimension is not active in mirror mode." This must be a glitch that MT did not foresee. Comments:
1) Design oversight: on level 7 (2:00-2:50), if a lemon lands on the center platform, there is no way to get it down without up-kick.
2) On entering level 8 (2:50), the green crystals appear before the level is done scrolling down ... but I think this is normal. One more reason the video is in fact real.
3) There is no way out !! That sucks ... Since they weren't planning to release the dimension, they didn't bother activating the vortex.

So even if it exists, this PD has no practical purpose, if you can't leave it.