Away from the cliff edge in Burundi, I came across the Rwandan National Institute of Statistics online and their surveys. It seems to have been around for a while, but I missed it.
The survey that immediately attracts my attention is a 2011 census of businesses. Given its size (123,256 establishments) I think it may be a comprehensive survey of business in the country. It is a useful complement to the detailed but small World Bank surveys on the country, as it (with luck) allows the diversity of companies to be explored in full.