I think the gist of it is that RBR want direct involvement in engine development (maybe even onsite?), and Renault will give them the means to do so through Nissan/Infiniti.
Come on people, use common sense... REN would wash their hands off any of those plans! They poured so much money into the development of the current power train, money they can only make back by selling as much of these engines as they can.
But of course they are going forward and throw even more money out the window to do it all again... /s