I was told that Ndizi are only the sweet bananas (which are mostly not cooked) and the green vegetable bananas are called "matoke". Is that a local thing (Kenya)?

The popular dish is called 'ndizi nyama' in Tanzania so it implies that ndizi could be used for green cooking bananas (plantain?) as well but i'm just a novice...

Matoke are also the green bananas for cooking in Uganda and there are vast plantations of these through which the train would pass on the way to Kampala. Ndizi are the yellow bananas.