You said: “What Onaka did was verify the existence of the certificate and the substance of the certificate (birth date, subject, etc).”
Where did he verify the substance of the birth certificate - for instance, the birth date? He verified the existence of a record which claims a Honolulu birth. The critical facts are gender, DOB, city of birth, island of birth, mother’s name, and father’s name. Where did Onaka ever say what any of those true facts are?
The PDF that Nero posted above this post verifies the existence of a certificate for Obama born in Honolulu. The gender is not verified but does not seem critical, nor does island since the city is verified. The time is there, but not the date and the date is critical. Not sure about the parents' names, why are those critical?
The most critical verified fact is that Obama was born in Honolulu. There may indeed be some sort of caveat that Onaka left out. So there are two questions in my mind, what are the legal ramifications of evasiveness if any. Second what would cause a 1961 BC to say Obama was born in Honolulu if he was not born there? What other process would create such a certificate? I heard theories in 08 about that, but don't keep up.
Regardless of the evasiveness in Onaka's answer, the most critical question of birth place is answered in the affirmative. Any theory that says otherwise has to explain how Onaka can legally say that.