There's a "Sting Ogawa" credited as the "sound composer" for SpellCaster:
http://www.youtube.com/watch?v=UtZOwZqFDNw#t=9m52s. So seems like that might be Sachio.
Based on
that, the "Sting Saito" who's credited as the "sound composer" for Super Thunder Blade could be him too:
http://www.vgmuseum.com/end/genesis/a/sthun.htm. Going with a completely made up family name would be kind of weird, though. The other possible connector there is that the person who comments on the Super Thunder Blade arrangement on
G.S.M. SEGA 2 is "S.O," and Ogawa is credited as "so" on the
VF4 Evolution OST.
Sega apparently did have another S.O., although it seems he only worked on one game ever.
UPDATE: Space Harrier 3D credits "Sting S" as the "music arranger":
http://www.youtube.com/watch?v=UoPJQYFK66Y#t=40m33s. So if "Sting Saito" really is Sachio Ogawa and there isn't a SEGA sound guy we don't know about named Saito, he's gone that way more than once.