Tips on fixing Disney store Woody?

I’m trying to clean up & fix my 21 yr old son’s old Woody doll. It is one which you activate the voice box by pressing his Sheriff star or shirt buttons. I finally worked the voice box partly out of the doll’s back and found a metal key hidden at the bottom of the box. Does anyone know what the key could possible be for?
Any tips on trying to reactivate his voice box & try to get permanent black marker off of poor Woody would be greatly appreciated! (I’ve tried goof-off but it didn’t remove any marker.)

Melanie Mc.