I don't know.

Here's an idea of how it could work, which isn't complicated, and which actually would produce the general speculated boot order for the rest of the game:

First of all, let's say Shawn gets booted in EP 6 (it could be any Drake though).

The Ghost Tribe of Lillian, Burton, Michelle and Shawn is brought in for the first challenge in Ep 7. J Pro explains (or maybe he doesn't) that if the Ghost Tribe wins, they earn the right for one of their players to return to competition -- and, one player from the losing tribe (i.e. the tribe that finishes third) will have to depart the game.

If the Ghost Tribe wins, the "legitimate" tribe that finishes higher (i.e. in second place) will receive the reward of making the determination. They will select a member of the Ghost Tribe to come back, and select a member of the third-place tribe to leave.

So the Ghost Tribe wins, Morgan comes in second, Drake comes in third. Morgan gets to make the picks (note that in this scenario it could just as easily have been Drake).

Well, with Lillian and three Drakes to choose from, of course Morgan would pick Lillian to come back. Then, in an ironic turnaround of diplomatic relations, Morgan opts to eject Rupert out of the game before he can start winning post-merge ICs.

Now we have a merge. From Drake, we have Jon, Trish, Sandra, Christa, who get pagonged one by one, leaving only Morgans as the final 6.

Tijuana and Osten start worrying about Ryan O. and Andrew as IC threats. They enlist Lillian and Darrah to vote those two out next. Leaving an F4 of Tijuana, Osten, Lillian and Darrah.

Some things could vary -- the pagonging could be interrupted to get Ryan O. out earlier and Christa out later, say. But there's the idea.