I think this is just about the only combination that would result in a non-legit sell out.
If any one of the Sydney teams were in it, it would probably sell out.
Newcastle and Canberra would both bring a tonne of support. (moreso Newy)
Even Brisbane and the Warriors would bring a heap of support.
What i would do is this.
Early in the season release all public tickets, let's say 62k (could be more could be less) to members of the 16 clubs for sale, so 4k per club.
As it becomes mathematically impossible for teams to make the 8, sale to them stops.
At any point throughout the season members can get a refund minus a small admin fee. Those tickets get reallocated to the pool.
End of last round, all unbought tickets available to the members of finals teams. This gets wittled down and reallocated when teams are eliminated.
Maybe along the way you release a portion to the general public but look after members first.
Haven't given it too much thought so this maybe completeltycompletely stupid.
The AFL could sell their GF three times over. We can't. That's fine but take it as an opportunity to look after people that genuinely follow the game.....members.