Originally Posted by
gnaget
That's going to be tough because SAS uses NW and the passenger has to obtain an invitation from check-in or the gate. So it's not like just informing the reception like at a *G lounge that you have a guest. You might have better luck with the RCC at IAD.
They could also hope that someone entering the NW WC there is a NW WC, DL CRC, or CO PC member, all of whom can bring in a companion.
(With such a long layover at IAD 11:30-17:20, I'd be tempted to head out of the airport.)