Which is fine. But trying to figure out why Oligarchians are referred to as Orcs is kind of pointless. So far as I am aware, only the Sirionites ever referred to them as that. And I've never, ever heard the term actually used IG.
Speaking as a former ruler of Oligarch, Orcs was just Sirion propaganda. They did call "us" that IG but "we" never referered to ourselves like that.
I think most just said Oligarchian(s).
Besides, the grandfather clause only allows Sirion to be anything else than humans. Oligarchians couldn't be orcs even if they wanted to.
