Diane Dimond had absolutely zero factual proof other than her own beliefs that Michael's children were not his own biological children, and frankly her beliefs are very white.
I myself am white. And I know from being white that it is often the idea among white people that if MJ was black, then his kids should have been black as can be. This is stupid.
Unfortunately, they fail to look at people like oh, Halle Berry, Mariah Carrey, etc to see what mulatto looks like, and also, 99% of the white population has no clue about genetics.