Okay, you are the only one I have heard this from - that there should be no trace whatsoever of this call except for from the router. Others will have to back up what you are suggesting because it doesn't make sense to me.
To clarify: the four components are:
ROUTER--->TW----->Cell Provider---->Cell Phone.
The records were found at TW, at the cell provider, and on the cell phone.
Cisco IT is not involved.