Just gonna leave here a tip for dealing with Foxy, especially on harder levels.
As soon as you start the game, keep going back and forth between the left and right sides of the room, opening the camera at the Pirate Booty every time you hit one of those sides.
The key here is how long you keep the camera open: after about a second upon opening the camera, you'll hear a sound akin to a pen click. That's your cue to close it.
Managed to stall Foxy until about 3AM like that. That's how I beat 4/20.
I gotta say, the plushies are very cute!