"Currently not employed..." ...Was she even fired?
Notice how Lucasfilm informed the world that Carano was currently not employed by Lucasfilm and that there are currently no plans to employ her in the future.
So was she even fired?
It stands to reason that a non-vital character such as Cara Dune would not require the actor to be signed on to play the role until the script is completed and production planning is under way.
Nothing in S2 told me that Dune was a central recurring character.
I get the feeling that Carano knew what she was doing. She just petulantly posted a bunch of shit so she could spin the reaction out into a martyrdom story when she actually had nothing to lose. Pathetic.