Money Moral Dilemma: My daughter delivered a wedding cake an hour late - should she fully refund?

Hudsville

Hopefully your daughter has Terms of Business that clarify her liability for exactly this situation, as it is a fundamental feature of an events product. 
And hopefully she not only incorporated her terms at quotation stage, reattaching them at order acknowledgement stage, but also drew attention to her liability (the 'what ifs') in her quotation etc, as bridezillas are rife, and probably won't read Terms of Business.

However, customer satisfaction is everything to reputation. How one deals with mistakes is the difference between staying in business or not.
Full refund & a bottle of Moet. Bridezilla is more likely to tell people that you dealt with it properly, ensuring multiple more jobs from her friends & their friends etc. 

Bookworm105

this is an MSE thread designed to provoke comments, "my daughter" is imaginary.
Those thinking they will get answers to questions are dreaming.
Those posting rhetorical questions are merely filling their time.