In order to relabel a Module Name the Module Name must appear in Module Customization.
The Contractor RFI module unfortunately cannot be customized and relabeled.
What does RFIA stand for?
If your documents need to be associated and tied to formal RFI's then you'll have no recourse. If your document does not need to be strickly tied to formal RFI's is it possible you use a module that is not being utilized on your site? i.e. Issues Module. This module can be customized and relabled. This module can be customized with new data fields. You would still be able to link other supporting documents like RFI's.