No. There has to be a bigger reason he’s hiding the real birth certificate.
You are overlooking something very obvious. His name is Barack OBAMA. If his parents weren't married, his name would be Barry DUNHAM. It would demonstrate that he was using that name for years, and he knew it was a lie. It would demonstrate that he had always been lying and misleading people, and that legally he is not President Obama, he would legally be President DUNHAM!
You have no idea how humiliating that would be to him to have to admit such a thing now. It would also have been ruinous had it come out in 2008, prior to the election.
Obama? Lying and misleading people? :-) He'd already had more than one name, several different Social Security numbers, etc. Besides, see Post 26. He's already prepared everyone for the possibility that his parents weren't married. Not worth hiding his birth certificate just for that reason alone, IMO.