I don't know but I can't imagine Nine would have been too happy to hear that they would be losing 1/4th of their Broncos games. Unless the NRL were intending to sell themselves to the highest FTA bidder, all such a move does is jeopardize the overall value of the next TV rights deal.
Personally I think it was a manufactured rumor/gamble to spook the shit out of Nine, thus milking them for everything they're worth. Kayo is growing exponentially as more and more people catch on to it and switch off their Foxtel because it's trash, so it wouldn't surprise me at all that the NRL see it as a valuable bargaining chip against the FTA players who are rapidly losing relevance in the modern world.