7 & 10 don't have to partner to break the rights up, it just needs to exceed 9's offer by the margin when combined.
There's too many scenarios where this can go to say 100% who will end up with what but yes 7 would like a piece of NRL. They are interested in either Friday nights (preferably) or Sunday afternoons to do a north/south split of NRL & AFL - if the price is right.
I do not believe that Saturdays will come to free to air. Monday night is a remote possibility. But both will be on the table.
I believe it will be a case of 4 games and 2 double headers on a Friday & Sunday and if a QLD team is selected for expansion you will see 1 team from there on both days to boost the Brisbane market. There will be at least 2 NSW teams on both days, if not more, particularly a local derby match. If 10 gets the rights, expect to see regular Storm & Reds games selected.
I believe there will be only 2 FTA broadcasters for home and away matches. Sundays in my estimation will be a toss up between 7 & 9 with 9 the favourite. Fridays will be a toss up between all three with 10 the favourite - in my opinion. Finals will be split between the two with grand finals alternating. You may see the loser from the Home & Away package pick up the entire rep slate or part of it but more likely the other 2 will lock that away too. Games will most likely be simulcast on Foxtel. The other alternative is that 9 will keep its existing slate plus get an extra Sunday game.
That's 100% speculation.