We don’t even know if he HAS a US passport.
If he has a US passport but not a valid US birth certificate I would think the only way he could have gotten a US passport is if he naturalized somewhere along the line. But the laws regarding passports are not my expertise at all so take that with a big grain of salt.
Given that two people lost their jobs for unauthorized access to his US passport records, it’s fair to assume the he DOES have a US passport.
To get a passport, the applicant must either present a US Birth Certificate or a US Naturalization Certificate. Nobody can apply for Naturalization until they are 18.
Now, I’m no legal expert but it looks to me like that means that he couldn’t have started the process until August 1979 and must have completed the process by July 1981 when he travelled to Indonesia.
However, he couldn’t have applied to Occidental and gained a scholarship to attend that college if he hadn’t already naturalized. So we’re out of time. He couldn’t have naturalized.
If he didn’t present a naturalization certificate for his passport, he must have presented a US birth ceritificate.