I give that story a -10 in credibility, and have since I first read it. In a word, it's nonsense. The so-called author starts off with the exciting story of Sr.'s witness of Mboya's assassination, followed many several graphs later with the admission that there's no proof of the story. To wit:
"...During a visit from his old school friend, Zane, in 1974, Obama confided that he had seen Mboya's killer and claimed to be the only witness who could identify him. According to an biography of Mboya, "Tom Mboya: The Man Kenya Wanted to Forget," nine eyewitnesses to the shooting failed to identify Njoroge in a police lineup.
Obama is not mentioned in the book. If Obama identified the killer, or tried to, press accounts of the trial are silent about it."
Then we have Susan Mboya's testimony that her father "was aware that Obama had a child in Hawaii, and was not happy about Obama's plans to leave his son behind," and "In one of a series of letters the two men exchanged, Mboya chastised his protégé, Susan Mboya said."
But for some unexplained (cough, cough) reason, "She declined to release the letters."
Uh, huh. Susan Mboya was an early supporter of Obama's campaign, but she didn't manage to get into the act, supporting Abercrombie's memories of the great love affair, until late September, 2008? In one story, in the Boston Globe? With no proof, other than her say-so -- just like the pulled passport, and Sr.'s witness of Mboya's death. It's all true, it's just that, well, there's no independent proof....
As mentioned earlier here is the 1960 “Time” article about Tom Mboya. On page 8 it mentions the “Jackie Robinson - Harry Belafonte fund” which Mboya oversees and which has already been used to send 81 Kenyans to the U.S. to be educated.
While Susan Mboya has refused to release her father’s papers, some of them may be among the personal papers and correspondence Mboya had with students who participated in the airlift. Those papers are at Stanford and personal correspondence is listed as one of the items in the holdings.
Of interest in the “Time” article, it mentions Pam Odede was sent to Ohio as one of the students. Pam would later become Mboya’s wife and I am sure it is no coincidence that their daughter Susan now lives in Ohio.
http://www.time.com/time/magazine/article/0,9171,894716,00.html
With your mention of the Boston Globe article, I noticed that it mentions the divorce of Sr and Ruth the previous year of 1973. According to all reports Sr and Ruth were married for a total of 7 years(which would put the year of their marriage at 1966) and yet from all I have been able to find out Mark Obama Nidesand was born in 1964 and David was born in 1969. Another part of the Boston Globe article which doesn’t ring true is that Sr’s two oldest children, Roy and Auma, lived with Sr and Ruth. This doesn’t fly in the face of Kezia’s claims that she didn’t know about Ruth until after the two ran into each other at the hospital after one of Sr’s many car accidents. It is definitely one extremely tangled web!