The symbols on the pillars at the House are used everywhere on the old stonework in Azim, albeit without the glow, and also on the modern banners and mats around the tribes' camps. I wouldn't be surprised if they're Allagan, since they're vaguely reminiscent of the crystalwork in the Labyrinth of the Ancients, but it and the news of a tribe predating the Xaela and Raen would probably mean that the Auri have the same relation to Allag that the Ixal do.