Shadow World Speculation: What is the Mazatlak Pillar City?

For those that have perused the extensive Shadow World timeline in the Master Atlas or Part IV: Lands will have seen a few references to the Mazatlak Pillar City. Call me intrigued! There are four references in the Master Atlas (I’m using 3rd Edition):

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  1. Mazzara Delta: [Cool Temperate/Seasonal] Y’nar (Mixed economies/Monarchy/TL: ) A vast delta/archipelago; this fragmented land and the shores to north and south are controlled by a Y’nari kingdom. At the head of this delta is the capital: Mazatlak Pillar City.