The files are stored in plain ADPCM encoding. It's completely documented, Dolphin devs and other people know how it work. The only unknown is where each individual SFX is stored, and where the decoding parameters are stored.
https://www.dropbox.com/sh/s34spz3nj6vqc6u/AAAyFTF3RtafB8xoP5OzG31xa?dl=0
EDIT: The data file is part of the game disk. The file in my Dropbox folder is an audio log file used for reverse-engineering, not the actual data file.
https://www.dropbox.com/sh/s34spz3nj6vqc6u/AAAyFTF3RtafB8xoP5OzG31xa?dl=0
EDIT: The data file is part of the game disk. The file in my Dropbox folder is an audio log file used for reverse-engineering, not the actual data file.