The wiki says that Shadow Freddy appears in The Twisted Ones

The wiki says that Shadow Freddy appears in The Twisted Ones Novel. Is this true? If so can someone please explain the context? Is that why Nightmare appears on the cover?

Shadow Freddy, Five Nights At Freddy's Wiki

RWQFSFASXC, Villains Wiki

Shadow Freddy, Five Nights At Freddy's Wiki

Five Nights at Freddy's Character Encyclopedia, Five Nights at Freddy's Wiki

Fnaf 3 Shadow Freddy by TheBlueLitten on DeviantArt

Freddy Fazbear, Five Nights At Freddy's Wiki

Five Nights at Freddy's: Second Generation / Characters - TV Tropes

Five Nights at Freddy's: The Twisted Ones, FNaF: The Novel Wiki

VS OURPLE GUY (Video Game) - TV Tropes

Freddy Fazbear (FNAF Books), Villains Wiki