Did you receive a datafile when you downloaded your project?
You can still implement a method from an interface without having any functional code in there, as long as the rules of overriding apply.
(...) but no where in the comments for these two methods is the word "must" used (...)
Ummm, I'm willing to bet that you don't know that. You are just assuming that to make your own life easier. However it is true that some beta versions of the assignment required candidates to convert data from one format into another, which required use of the create() method.
[this method] is left over from a previous version of the exam.
Any methods that throw RecordNotFoundException should do so if a specified record does not exist or is marked as deleted in the database file.
candidates have passed without implementing the create() or delete() methods.
The java.lang.UnsupportedOperationException might work for you in this case.