I think we can eliminate that one lone entry from Kenya into the US as having anything to do with a birth in Kenya for zero...
Omar attended Class of 1966. The kenyan graduated from Hawaii July, 1962. The arrival record goes to July 1962. Omar commences classes in September 1962, the Kenyan commenced Harvard at the same time. They shared accommodation:
http://articles.boston.com/2012-01-08/metro/30602200_1_president-obama-barack-obama-kenyan-family/3
“...The only African student at the school, Obama stood out in a number of other respects. Not only was he three years older than most of the boys in the sophomore class, his arch colonial accent immediately marked him as different. That he initially lived with his brother in a rented apartment in Cambridge, a place often churning with visiting Kenyan students, added to his exoticism. But within a few weeks the normally reserved Obama had made a large number of close friends, many of whom remember his sunny disposition nearly half a century later...
Page 5 of your link ...
“Mboya was an ardent advocate of education and the organizer of the famed airlifts of young Kenyans to the United States that had brought [Uncle Omar] Obama to Boston, according to a list of the 1963 airlift participants in Mboyas records at the Hoover Institution in Stanford, Calif.”
Uncle Omar arrived in the U.S. in 1963.
This story creates more questions than it answers. It says Barack Sr. contributed $300 for Omar’s travel expenses. This goes against the idea that Barack Sr. was a broke college student who couldn’t afford to go back to Kenya. Second, it says, “Omar was directed to Browne & Nichols, a prestigious private boys school, by Ellen Frost, a friend of the elder Baracks whose father was the preparatory schools treasurer.” How did they have the money to send this kid to a private boy’s school in the early 1960s?? And then if the place was “often churning with visiting Kenyan students,” it seems the INS records would show a lot more aliens embarking from Kenya.