While I completely believe this story, makes no sense to talk about "African courts" in general. AFAIK Uganda and Nigeria are countries far from each other, with different forms of government and even different ethnic groups.
Yes, I've been there and this your assertion is simply not true, unless by "similarities in culture" you mean they are all human. Heck, there's ridiculous variety of culture in the same country - South Africa has 11 official languages, if we are to take language as a proxy for culture.
If you think all sub-Saharan African governments have the same levels of corruption, you're plain wrong. As an illustration: (in no particular order) Nigeria, Botswana, Kenya, Rwanda, Zimbabwe have corruption levels that range from "it's expected in every official interaction" to "you (civilian) will wind up in jail if you bring up the idea of a bribe". So there's nothing that's inherently African or cultural about it.