Well, look who I found:
Masahiko Ishida
According to his myspace he worked on Image Fight and R-Type 2, and lately in Metal Slug SV001 (slot machine)
So this man is the ex-irem OH!GI and still works in SNK as CHANāGON. From SGZ era he is probably either Hori_Hori or Q_Jirou (possibly the former) but I haven't connected all dots.