Yes, I agree they were rescued by McMurdo personnel, but where were the personnel that General Hammond said would arrive to secure the site going to come from? He certainly made it sound as if they would be SGC personnel.
He must have been quite busy on the way to the Antarctic.
I've also wondered about telling a sergeant to call McMurdo and give them orders. What's he supposed to say, "I'm Master Sergeant Harriman and General Hammond says to search these coordinates."? I can just imagine the reaction.