It wasn't his choice to make.
Sorry, but that's not making sense to me. If the claim is that he was born in Mombasa, there has to be some evidence or at least good reasoning to support it. Mobasa was 200 miles further away than Nairobi, which was the capital and had hospitals. Mombasa was harder to get to, as well. So if you're going to argue for Kenyan birth, why Mombasa instead of Nairobi?