I felt the need to correct many things in ToA, one of it is the Chultan people being so ridiculously enclaved. Of course, Chult is a very dangerous place and there’s this whole bizarre thing with the spellplague and Mezro the city in Heaven (ugh!) but still, where are the Chultans? Apart from Port Nyanzaru, not a single village?

Anyway, this has all been said far better than I could by POC Gamer:

https://pocgamer.com/2017/10/13/tomb-of-annihilation-review-part-1-chult-in-5e/#more-573

My own solution is to introduce a diaspora. Chultans that left Chult generations ago when disaster struck and (lets keep it simple) the earth shook and spat fire… But now, with the disaster long behind and the recent successful ousting of the invaders, things are looking less grim. Maybe it’s time for the exiles to return?

As Port Nyanzaru doesn’t look like a city that can be expanded easily, another site have to be found.  That’s a mission for a Chultan PC!