That's not so. Degrees from universities in high income countries are often preferable in low and middle income countries, but they are nowhere close to being the only acceptable ones. Many people in such countries earn degrees in other such countries and use them just fine in their country of origin or even to emigrate to Western countries. For example, my cousin in Dominica earned his degree in Geology from a university in Cuba, since he got a full ride there, and now he works for the water utility back home. For another, many students from French-speaking countries in Africa will go to Morocco or Senegal for study, and I know this because a good friend of mine from Mali is going to do a Master's in Accounting in Morocco instead of the U.S. because it's a faster track to CPA in his home country.
A fake diploma from a poor country has no value in a poor country. US or European degrees are almost the only acceptable degrees in poor countries.