Can Mvemba a Nzinga win religious victory?

Mvemba a Nzinga, the leader of the Kongo civ, has the following ability:

Religious Convert

May not build Holy Site Districts, gain Great Prophets, or found Religions. Gains all Beliefs of any Religion that has established itself in a majority of his cities. Recieves an Apostle each time he finishes a M'banza or Theater Square (of that city's majority Religion).

Does that mean it is impossible for this civ to win using religious victory?

I believe you are correct. Unfortunately, because it would be hilariously awesome if it were possible, Mvemba a Nzinga cannot win a religious victory.

In order to obtain a Religious Victory, you must make your Religion the predominant Religion for every other major civilization in the game.
- "Religious Victory", Civilopedia; emphasis added

I understand this to imply only the creators of a Religion are eligible for a Religious Victory condition. If Mvemba a Nzinga spreads the religion of his cities to other civilizations, he is helping the creator of that religion advance towards a Religious Victory, not himself.