Sorry as I know you posted this some time ago. However as the CQ has no number assigned to it, it should not be possible to call directly.

I have always liked the fact you can visibly see how and by what option a call has made it through. However that is more on the receiver side.

However I have never looked at it from a call being made to an AA internally, just as an external way in.

So not sure if you have got anywhere with this since posting as I can see the need for what you are saying. I will have a play and see what I find.