Since the surges pull in people from the Exile Lands, perhaps Funcom can utilize this Thematically for travel to Siptah.
What if the tornado/portal feature randomly spawned over specific biomes in the Exiles Lands. If you walk under it, you get a message that states you will be transported to the Isle of Siptah in 20 seconds unless you leave the area of the portal.
There could also be a warning that pets and inventory will not transfer, only items worn or carried in ready bar.
There could be a merchant who sells passage to the Exiled lands on Siptah.