Which makes me wonder why we don’t have more vehicles run on Diesel generated Electric power.

I've wondered that too (especially as the owner of a diesel car). My best guess is that hybrid drivetrains come at a price premium compared to plain gasoline engines and Diesels also come at a price premium compared to plain gasoline engines, so trying to put both on the same car would incur a double price premium and not enough people would want to pay it.