I think they would likely seat a larger group on the upper level where they can move tables a little to accommodate. You could ask at the desk though, but if they are busy it might be more difficult. Of course, if you seperate, there is no guarantee you will all be seated at the same time. Now, the last few times I've been to GG it's bee pretty chill and not crowded, so it might not be a problem at all, but I'm sure it can depend.