If you change the file extension to .zip you'll be able to explore the file as you would any other archive, from here I guess you could rename any duplicate files and then resave with the c3p extension
Having a look now, I can't see any duplicate file names, but there are 100s of animations and I've only skimmed
EDIT//
Scanning with CCleaner states there aren't duplicate filenames, however I guess in-engine references could be different.