So the primary appearance of the 半澤一雄 name is in conjunction with works by director Satoshi Kameoka and his company/brand/something Silentvision:
https://web.archive.org/web/20050307...le_D.N.P..html. (It does also appear, randomly, for composition of Mischief Makers's vocals.)
Every time Hanzawa's name is listed in English in a Silentvision work, it's romanized as
Ichio, not Kazuo. On
the website, on
videos, and even on a CD (DIGITAL NATURE PARADISE, which I'm going to add in a sec).
So I'm not sure that "Kazuo Hanzawa" was actually ever correct. Thanks again, GMCL! (
Though there is a stray credit to "N.KAZUO" in Konami's Cue Brick.)