((LB was asking about the final session of this campaign Mirg as there is one left if we want to play it out. If we do play it then you can change your mind and have it so Rogha traveled off the island with them, which could easily be because the crystal took her regardless of her decision. If you don't want to do that you will probably have to sit out this next session and when Chult begins, which I don't imagine would be for some months yet, you will need a new character.
The Chult campaign was originally a follow on from the Aldera campaign for the good guys. They saved Aldera and left to do some more good, but when they left they were shipwrecked on Chult. It's a follow on but does not connect to the Aldera story except in that the same party went through it. They then went on to do the same again, sans shipwreck, in Immortal Vengeance.
As far as next session goes I'd like to see Aldera afterwards, not least as the DM has prepped it and I know how much trouble that takes.

But the ending last session did lead nicely into a Chult option though so if I'm outvoted I've no problem with it.))