Thanks for pointing out the sound files in the btl folder. I just played my undub copy for about 30 min and it's perfect so far; all Japanese audio on cut scenes, skits, and victory quotes and all the text in game, menu, tutorial, etc are in English. Just to summarize what I did:
Patched eboot of US version
Japanese movie files
US RootR.cpk with the following files from the Jap RootR.cpk: snd, btl/acf/skt and btl/acf/vav files, chat/chd files.
With all these put together, I think this time I really might have a 100% undub version of ToGf.