re: Is this pretty much proof that Rettig is out as well?

Well Cameron coached Antwan Randle El at Indiana so I'm sure he is interested in using the best talent he has available to be successful. If that's a dual threat, read option offense, then so be it. He'll still find ways to get his WRs involved. That's actually the great thing about Cam. He's adapted multiple offenses at different levels based on his players' skill sets.