I've been a member here eleven years. Owned three Crossfires - several people have replaced starters only to find it was not the starter.
RCMs cause "no starts" so often, we have a thread dedicated to fixing them, but if you are good with throwing money and time away, crawl under the car, passenger side, back by the "bell housing" and you will find the starter.

From what I read in your post, it is either the RCM or SKREEM. I can't tell you which, as you imply the starter never even engages - that is an RCM issue. But you then say you hear it twice, then nothing, THAT is a bad SKREEM. But again, you won't just hear a click, you will hear the starter engage, this will happen twice, third time, you get nothing. Yank battery cable and reconnect it, you get two/three more tries then nothing.

If the starter NEVER engages and turns the engine over, it sounds to me like a bad RCM.

If you REALLY are hearing a click - is it coming from the top of the engine or the starter solenoid? If solenoid I might suspect starter, but I'd be more interested in watching battery voltage as well. I sharp did in battery voltage will cause the ECM to "kick out". In these cases, you simply have a bad battery or REALLY corroded/loose battery cable connection somewhere.

I can't tell from your post exactly what you are chasing.