Yes, he was.
Then again, I think TKOS has the biggest number of former members (198!), and I can't put a post about everyone. Yes, Okocha was a high ranked member of TKOS, but there are some other former members with such rank as well who I have not mentioned. That's mainly because I know very little about the times they were active, and can't really say what kind of impact they made to TKOS.
And even that there are some people who I know would deserve at least being mentioned, such as Azey, I have chose not to.