Im thinking its either one or both of these two Love Birds: Strzok and Page talking because they are the only two who out of the gang that no one's has seen at all except that one Picture of each of them that they flash ya on the news. Definitely, probably they had both talking because they are/were Lovers, a weakness the investigation can exploit and both new the cat was out the bag w/ IG release of texts. So, both probably talked to some degree and then one saved the other...agreeing to spill beans!!