When you do your external you can also move the rudder full deflection left and right - this doesn't prove that it will move when you push the rudder pedals of course, they may have become disconnected, but at the same time move the elevator fully up and down.... and make sure the rudder doesn't bind against it when it is against the (adjustable ) rudder stop, or more to the point make sure that full rudder deflection when recovering from a spin isn't going to inhibit what you want to do with the elevator, or v-v.
( if the rudder travel can be adjusted, it can be adjusted wrong. The most dangerous aeroplane to fly is one that has just come out of maintenance. )
Murphy is always with us.