Sorry for the late answer, I don't use this a lot,
Probably you already beat it, but, Freddy moves every time she laughs, the last one (when she is eating, the cum) takes around 30sec or more for her to attack, if she is already there, she won't leave, so all you had to do, is save battery, remember that everytime one of them is in the hallways or besides you, they make a sound when they move, so you only have to keep checking on Foxy
Btw, the louder the footsteps when they move, the closer they are, 3D sound will tell you who is moving, right is Chica, and left is Bonnie, try turning the volume is you cannot make a difference