I kind of disagree. I see Rob and Amber having no problem lying to or backstabbing Lex when it comes down to it. They will make the right strategy play if they have to.
It's not just Shii who's in trouble, but all of Mogo Mogo. The thing that Mogos have going for them is that they can vote as a block of 3. With 9 people left, they only need 2 people to control the vote.And Kathy and Amber hit the nail on the head in saying that Big Tom is the perfect neutral vote. If the F5 are as Amber proposed to be (Kathy/Lex/Romber/Tom), then Tom is the swing vote. And the smart move is to take Kathy/Lex, because everyone knows that Romber are taking each other to the finals. Plus either Rob or Amber will win F3 immunity over Tom, so Tom has to take Kathy and Lex and hope that one of them will take him.
Shii may have some semblance of safety by picking Rupert to have her one-on-one with. She planted the seed of how dangerous Rob will be in individual immunity, and Rupert already doesn't like Rob (though he tolerates him). Rupert has been spending fishing and working time w/Tom, so those 2 may be pretty tight. Mogos can team w/Tom and Rupert to get rid of Rob.
Plus if Alicia is next weeks boot, then Mogos with Rupert/Tom can take out Rob to put the game on an even playing field.
The best moves from here are:
Alicia
Rob (too strong)
Lex (last skinny man)leaving a final 5 of Kathy, Shii, Jenna, Rupert, Tom. But I don't know that any of this game has followed good logic.