In my opinion, the only way the house can be shaken up in a major way is if either Zach or Hayden re-enter the house. Zach can cause trouble and Hayden can win comps. Then Donny needs to win HOH, assuring either One of the guys running the game goes home. Otherwise, this twist will have no impact on the game.
Also, I wonder if Frankie will ever realize Derrick is only truly loyal to Cody, and he is just using Frankie to do his dirty work. I doubt it, as Derrick is far and away the best player this year.