I didn't get the impression they were the same tribe. Was there something specific that you thought indicated they were?
I also don't think you can talk to anyone after
the land is cured, as the cutscene showing that plays as we leave permanently for Baldur's Gate, so I assume that at most all we can do is avoid that area and headcanoon it. IIRC, they are when we meet them, so there's no chance to do anything except fight or run away.
