Yeah, it's a scrapped draft of OG The Freddy Files. It was confirmed to be real by Entom.
Sadly the whole situation around it is such a mess.
And I would like to say, don't use any info from it as 100% canon or confirmation for theories or whatever. So much has changed since then, and many of the current story elements were changed. Yeah, some things were kept (like William not caring for his kids, and Bite Victim's being "shattered") and some were reused in Fazbear Frights (Emmett Tucker was reused as major character in "Find Player Two!" story, Dr. Talbert in epilogues, although heavily changed, and Michael's nickname after scooping was repurposed as a completely new character, the Stitchwraith). You can use it to look into how Scott writes the story and to better understand our current story.
Basically short version, if you want to read it, then the only thing you can use in your theories are Afton's characterization in his monologue, and locations of each establishment. Everything else was, or could be, changed.