Hm... I don't think there's enough there to suggest Zauz' link with the Cobble. It seems unlikely that only the Cobble were involved in defending thw WotOK.

More importantly, sure Zauz' ancestors made the sword before or whatever- what evidence AT ALL is there that the Cobble made the sword? Because they hold one of the metals? Then look out guys cause looks like the Anouki are also Zauz' descendents. Maybe they're Gerudo crossbreeds.

And I scanned the text dump and couldn't find anything from Astrid about the Cobble...