I'm planning on GM'ing a one-shot on Wednesday, the day before the convention officially starts. It's not an official event. When I asked earlier, people suggested that the easiest way to do this would be to gather my players, show up at one of the HQs on the day and ask for a table. So that's what I'm planning to do.
The question now is: two of my four players do not have badges, because they hadn't been planning to attend GenCon. Do they need one for Wednesday? I looked for some way to buy a Wednesday pass for them, but couldn't find one. I want to make sure that everything's kosher and we're all good to play.