Out level a zone??
I would normally suggest using the addons Wholly and Grail to see what quests you should be able to do and where the quest givers are.
There are several breadcrumbs for Vashj'ir that aren't necessarily obvious past 80, but all lead to "To the Depths," which is what gets you on a ship bound for Vash. For both factions, the quest happens at the harbor, which for Horde is Bladefist Bay, just outside of Org. Head out there and check to see if Commander Thorak has the starting quest.
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