Was this authorised by QNTM?

I think all SCP content is creative commons share alike (https://creativecommons.org/licenses/by-sa/3.0/), so I don't think he actually needs to -- assuming this is based on SCP and not the book. I know the book had some revisions done to make it legally distinct from the SCP stories for copyright purposes.

In one of the youtube comments the director says that they contacted the author and got permission.