Most material I’ve seen presents the tribal confederation’s city as the local trade town, and each clan having its own central settlement, sometimes - but not always - a hillfort. As to there being a settlement that is the seat of the tribal “king”, not so much a thing since the tribal king is a member of one of the clans of the tribe. And the king’s “court” moving between the settlements of its member clans.
But - if you’re creating your own clan and such for your own game - my tip would be to take an eraser and “de-canonise” a whole tribal area for your game, and then create what you want. For example, in a past game I pretty much erased everything written about the Dinacoli tribe (not much really) and put in my own clans and settlements.
In your case - creating a central trade settlement for your tribe’s feuding clans isn’t world-breaking - just the way things are done in that tribe. And if MGF for you is a tribal king as an ageing vingan dressed in piecemeal armor, the tribal champion is a great troll who carries its human “master” around, and tribal justice is dispensed by an ancient artifact in the form of a “wheel of justice” - then why not.