Survivor Tony B was having a really hard time with FB log in, and fixed, while also documenting his steps in what it took to fix the problem. Mind you this is a FB problem, not a Survivor Z problem.
Go to settings, Facebook, click on your account/name, choose delete account, choose remove contacts etc.
Uninstall Facebook application and survivor z.
Restart phone (menu & powerbutton until Apple shows on screen).
Install Facebook, login in the app.
Goto settings menu, Facebook, login into account, now it won't show the survivor z app being allowed to use Facebook.
Startup survivor z, it's going to ask permission for using Facebook, just allow and you are one happy survivor z gamer again!