I don't know if the government of any African country have adopted the system of paying salaries in Bitcoin,
You could do your research on that. As far as I know, Central Africa Republic is the only African country that has made Bitcoin a legal tender. The rest of Africa are neutral about Bitcoin.
Since it has to do with the government another agency can be set up in the country in respect to paying salaries as Bitcoin which will somehow help in the growth of the economy of the country.
Help me understand how paying workers in Bitcoin will help fasten the growth of the economy.