It is a play on words. There is a song as explained by Wikipedia: Hello Muddah, Hello Fadduh (A Letter from Camp)" is a novelty song recorded by Allan Sherman. The melody is taken from the ballet Dance of the Hours by Amilcare Ponchielli, while the lyrics were written by Allan Sherman and Lou Busch. (You could look up the song, it’s cute) In the episode they change the word mutter(mother) to gutter which refers to when you throw a bad shot in bowling and the ball rolls down the side gutter and misses the pins.

Fadder is most likely also a play on words. I’ll let someone else respond.