I wonder how a random Russian would be treated in the streets of Cameroon...
Somehow, that angle is rarely discussed. I imagine if he/she were a landowner, the property would be taken by the state. Getting shot, burned alive with a tire around your neck, raped is not out of the question.
Russians seldom go to Cameroon. There is some African tourism (Tanzania and other countries), but I've never heard about the problems like you mentioned, only about tropical ilnesses...
Anyway some people from Russia emigrated into South Africa, but not very much.