G'raha Tia has the same tattoo the other Scions (Moenbryda included) have. Maybe not a Scion, but definitely a part of the Circle of Knowing, or Student of Baldesion. Also once more, he locked himself inside of the Crystal Tower, which only he (on the Source) can open and close the doors to, since he has (royal?) Allagan blood. The Unei and Doga clones are still within the Void/Thirteenth Shard.

Also here's Seeker of the Sun lore regarding their culture (word for word from the book).
The Seekers of the Sun are a highly patriarchal culture, with each tribe centered around a strong breeding male (nuhn) whose duty it is to form a harem and lead his people to glory and prosperity. Young males are born and raised as "tia", and must either assume the position of nuhn by challenging and defeating an existing nuhn in single combat, or leave the community to find a harem of his own. In particularly large tribes, multiple nuhn may coexist in the same community, though such cases are rare.