English voices are the original voices. DQ8 jap on ps2 had no voices, it was added for localization. You can't restore something that was never there until a port.
First thing, in your quoted message it says "Japanese voices restored", not "Original voices restored", second thing 3DS version is dubbed in japanese, this thread is about to restore the voices on 3DS version, not PS2. And no, english voices are not the original ones. In Japan it wasn't dubbed on the PS2 version because they prefered it like that, and they did it again with DQXI, to keep that "classic", mute style, but that doesn't mean that the first country that dubs it is the original creator of the dub, the game was still made in Japan and it had japanese text, that got translated,
edited and THEN dubbed in english.
Either way, original or not, you don't need a pass to play a game in whichever language you want.