I read on reddit someone called showclix and was told was told that "they will not be getting any more tickets issued for the event by SE, and they sold all available tickets with no plans to sell or reissue any tickets sold already. They also said any issue with access codes needs to be taken up directly with SE, as they just use SE's software, and all of that is handled by SE directly."
I can't say for sure this is true but it does worry me.