In the GA3 liner notes, Hataya mentions "Maeda, Oguro, Sawada, and Hataya" in
some context. It seems likely that he's listing the members of the sound team, but I don't know what the rest of the sentence says so that's not at all a definite.
The game wasn't listed on Tomonori Sawada's Wave Master profiles, so it is possible T.S isn't him, yeah. It was never in Tomoko Sasaki's lists either, though, including
the current one on her blog.