While I cannot prove the negative from personal knowledge, I think we can be assured that such a gambit–President George W. Bush leaning on Kenya’s President Kibaki using the leverage of American foreign assistance to Kenya to investigate Barack Obama as the potential Democratic nominee in the next US election–did not happen. But absent some sense of “boundaries”, a recognition of a difference between the foreign relations of the United States and the conduct of personal affairs and partisan political campaigns, why not?
See “My writing on my experience with the birth of “Birtherism” and Trump’s foreign policy.
Here is my piece from last year in The Elephant discussing the origins of Birtherism in the 2007-08 election campaigns in the United States and Kenya and their enduring legacy in American politics: “FROM BIRTHER TO MORE OF THE SAME: American foreign policy in the age of Trump and its impact on Kenya.”
See also American diplomatic perspective on Obama’s Kenya visit and a few personal thoughts.