The best way to share these things is to either release it as a patch or installer that can be applied to an existing audio.dat or to release the sound effect alone and instructions on how to add it to audio.dat. As a general rule, we don't allow full data files to be shared because in addition to your modded data, they include a significant amount of copyrighted data from the original game as released.
It might be a bit overzealous, but given Square Enix's history of shutting down mods and the fact they haven't taken action against this site, it seems to be the right decision.