So I got some comments from hannahmarie1313 and
Crypsalis which both state that the endoskeleton can be foxy as well.
Why I chose golden Freddy is because the phone guy stated that someone stole the "yellow bear suit" this may clarify that either there is another golden Freddy suit or the nightwatcher found golden Freddy and managed to shut him down which in the 2 FNAF game golden Freddy has a exoskeleton. Since everyone has lots of theories comment in the box whether it is foxy or Golden Freddy.
