I think the tribes are getting close enough to merge to already be considering removing muscle from the tribe. (Seeing Cliff gone will bolster those feelings.) I don't think that keeping strength will be a consideration for Nu-Aparri. They will be all about keeping alliances strong.
And while it can be stated that Alexis ruined her own game by volunteering herself as a fourth, she was the only one visibly making a deal with the brains.
Neither Morgan nor Sarah were even witnessed talking to any of the brains.
Why would the brains trade out a known outcome for one where 2 of their numbers aren't predictable?

Something else to consider. When plans are shown, it's usually Alexis that voices them, making her the defacto decision maker. It wasn't LJ's decision to boot Brice, even though we saw him voice dislike for him. It was Alexis.
With no one specifically aiming for Alexis, we will need to see the outcome of her scrambling in a positive light.
Morgans short-term story is tied into Jeremiah (long-term with LJ). And while Jeremiah was seen at least talking to the lady-brains, he wasn't really offering his assistance for anything other than getting rid of Morgan.

My thought is that the Press Image from above showcases the 2 "zombies" for the brains to use, leaving Jeremiah and Sarah as TC fodder.