In this case, sworn testimony could provide little but hearsay.
Subpoena the docs.
Sure. Call in his family fi you want. Some of them said he was born in Kenya. That’s fine. But the most important thing here are the docs.
There’s no need for a subpoena. Obama (PBUH) can and should simply authorize the schools to release his transcripts and the State of Hawaii to release the long-form. Problem solved, everybody happy.