Rand (likely after consulting Alivia) will come up with the plan, like he figured out how to Cleanse saidin from the Aelfinn's answer But as said, maybe Rand making this decision will be influenced by the last group meeting, especially Moiraine's "return from the dead", but e.g. also Elayne's pregnancy.

And of course the support of the other characters is needed if the plan shall work, namely that important people like the Amyrlin, the Seanchan Empress and the Queen of Andor declare Logain to be the true Dragon Reborn.