is it possible to beat well in your case 999/999/999/999/999/999 or more mode
I dunno if it is possible to beat the game on insane with all of the animatronics. I think probably not, since animatronics like Foxy and Mangled rely on the same mechanics, making multitasking between the two very difficult if not impossible.
That said, it would be very impressive if anyone could beat the game with all animatronics on insane difficulty.
Thanks for playing!