"Mumblefuddles" is not a real word with a defined meaning. It's a nonsensical word that is often used as a humorous or playful way to express confusion, bewilderment, or a lack of understanding. It's similar to saying "blah blah blah" or "gibberish."
If someone says "mumblefuddles," they are likely trying to be funny or emphasize that they don't understand something.
