Answer:
the purpose of this scene is to bring Kathy back into play. The filmmaker wants
to shock and amaze as well as excite the audience that Kathy is back. I believe this function was most definitely achieved because I was very shocked to see Kathy behind the camera and excited at the thought that she is back in Dons life. If I was the filmmaker the only thing about this scene I would change is the song. The reason for this is that to me the lyrics make no sense and the actor who is singing honestly hurts my ears.
Explanation: