I'd recommend that you go ahead and submit the games. Once general registration opens up you should have a very good idea of the level of interest out there.
It is no secret that GoT is big. Personally, I'd think you would have no problem filling seats at this table.
The best way to gauge interest in Numenera is to put the events out there. In the unlikely event that we can't fill the tables for multiple Numenera games, we could look into consolidating the games to get the number of players/game up. I doubt it would come down to that though.