Visitor Visa - B2

My good people here, I stumble on this useful site. A closed friend need urgent advise. He did is masters online in California and graduated last year August, the school has invited him and his family for graduation ceremony this May. He has paid the visa fees and filled the online form. Waiting for his interview feb 21. But something came up. He recall Sometimes in 2003 his late uncle brought a lady from u.s and they did court registry. Along the line the visa wasn’t issued and no biometric then. He has actually forget that incident existed and couldn’t even remember what really transpired then. He has travelled to 7 schegen countries, and others. All he could recall was, the passport name then was okaka Alexander. But he has since been using another biometric passport which is okaka Alex Omo and the date of birth change too frm 04/06/1979 then to his real age 04/06/1974 . He didn't even know why they has to reduce his age then. But now He has already filled his form that he has never apply before and he has no body in u.s. nothing he can really recall in that 15years ago incident. He is doing well in now. Please advised