Dodoma Wine Festival in Dodoma
Dodoma Region is confirmed as the entire base of the Tanzanian wine industry, the second-largest wine producer in Sub-Saharan Africa after South Africa, giving strong industry grounding for a Dodoma Wine Festival, though no independently confirmed event by that exact name and date could be located.
Wikipedia's entries on Tanzanian wine and on Dodoma Region confirm, in clear and specific terms, that the Tanzanian wine industry is based entirely in Dodoma Region and ranks as the second-largest wine industry on the African continent, behind only South Africa.