Final answer:
The name of the mess hall at Camp Whatsitooya cannot be provided without additional context or source material as it is not a widely recognized or officially licensed name in media or literature.
Step-by-step explanation:
The name of the mess hall at Camp Whatsitooya has not been provided in any widely recognized or officially licensed media or literature. Typically, when a question like this is asked, it may refer to a specific context or source material such as a book, movie, television show, or perhaps a lesser-known story or anecdote. If this reference is from a specific story, please provide more details or clarify the source so an accurate answer can be given. Camp Whatsitooya could be a fictional setting from a children's book, TV show, or movie. Without additional context, I am unable to provide the name of the mess hall.