GM badges do not provide any special access - they function just like attendees badges, so if any of your staff need to get into the exhibit hall early or late, you will need to assign them exhibitor badges.
Otherwise, any badge type will suffice, basically.
And a GM badge should not be required to enter the event hall on Thursday morning. It should simply be open at 7 am for GMs and players to enter, set up, and sort themselves out. If you are stopped, just explain that you are running a game and they should let you through.
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