Okay, we have reached critical mass: enough of you have expressed uncertainties and/or requested extensions, so I think the best thing to do would be to give the whole class a one week extension. If you are in touch with anyone from the class, you might want to make sure that they know.
I appreciate all your feedback (and please keep it coming). This is the first time I have assigned such a project, and I think there have been some growing pains.
(Oh, and one further thing: when making your case to the Library as to why they should buy the books you are recommending, you could mention the number of courses in which your writer might figure, across both campuses.)