Although Shogungen (Junior Assistant Deputy General) Tota ARIMA told that he was still a hatayaku (flag man) at that time, the discovery of Okadake monjo (the Okada family's documents) confirmed a common view that he was the Daigungen (Senior Assistant Deputy General) of the Government-general of the Tosando Force.
小軍監有馬藤太の証言によると、当時香川は旗役を務めていただけだったとも言われるが、岡田家文書の発見によって、通説通り東山道軍総督府大軍監であったことが明らかになった。