The 47 Ronin and Fujii Matazaemon

Does anyone know how I can check if Fujii Matazaemon (the Ako
Asano Family Advisor in Edo) who was there when the whole "47 Ronin"
thing went down (but was not one of the 47 ronin) ... is there
anybody here who would know how to check if he was related to the
same Fujii family which comes out of Hiroshima/Okayama prefecture ?
This is the same Fujii family which Fujii Kogen and Fujii Taroemon
came from. This is also the same Fujii family which the majority of
Fujii these days come from.

Fujii Matazaemon's son , Fujii Umon, was executed by the Tokugawa
Shogunate because of his involvement with the Meiwa Inncident (The
first real movement by western families to bring the Emporer back
into power and oust the Tokugawa Shogunate).

Any info is appreciated.

Thank you.