Complex sentence: It was later confirmed by Campus Executive Chef Antonio Pignagrande and Meliora Executive Chef Brian Mattice that that was not the case but that the recipe had been incorrectly entered into the University recipe storage system.
Split into simpler sentences: It was later confirmed by Campus Executive Chef Antonio Pignagrande and Meliora Executive Chef Brian Mattice that that was not the case. The recipe had instead been incorrectly entered into the University recipe storage system.