My theory is that the into the pit GAME(not novel)is not cannon in the universe of the game but in the novel's universe :

In the school's classroom, you can see a map of the world, but on it, some country are gone:

Florida, Europe, Iceland,Antartica and the most important, Mexico. You may think that on the FNaF universe, theses country doesn't exist, but remember El Chip, he's an beaver animatronic on the Mexico theme, and on security breatch, there is a full area on the Mexico theme!

So i think that the game is semi-cannon, or cannon on the novel's universe.

What are you thinking about this?