I think the reason why the request was denied in the past is because all of the Nigerians On Bitcointalk speak English and admins probably didn't think a Pidgin English board would have many users. But if the number of Nigerians is much higher now, it makes sense that you guys have your own local. However, if your local would allow users to write in English as well, the admins might turn down the idea. A Pidgin English only local would have better chances.
I think you are correct, and to add, and some may find it new, pidgin English is not a language thats familiar to Nigerians alone but some African countries, such as Ghana are familia with the language, and they maybe excited to connect since we not only connected by the language but by distance.