Stagg Field was not only given as a location, it was shown on the hotel map that was printed inside the gate-fold covers of the pocket program book. The putative location of this nonexistent room was on the Bronze Level of the West Tower, right next to Soldier Field (which does exist). You can go to this URL: https://www.chicon.org/hotel-maps.php, scroll to the bottom and you will see the same map that was printed inside the pocket program book, complete with the supposed location of "Stagg Field" (squint hard, the image is faint and the font is miniscule - and it isn't a whole lot easier to read on paper, either).

I would expect a middle-school bully to find it amusing to send a disabled person on a painful quest to locate a nonexistent room. What I did not expect was to find middle-school bullies running WorldCon.