Thats kinda exactly what we are saying ...
Talking with kithrak should contain this endings and consequences:
1) He find out about our parasite, but NOT about the box ...
he orders Beretha to kill us and search our bodies just in case, and leave to continue his search for other survivors ...
2) He dont find out about our parasite, nor about the box ... we agree on helping ...
he orders Berethe to return to her duties, leave to continue his search for survivors ...
3) He dont find out about our parasite, nor about the box ... we dont agree on helping ... (You are useless to me scenario.)
he orders Beretha to kill us and search our bodies just in case, and leave to continue his search for survivors ...
4) He finds out about the box (it bugs me a little that in this scenario we cant block out his Detect Thoughts)
he orders Nathanos to burn us to death ... either instant game over, or impossible fight starts ... feel free to make dragon imune to Fire damage so clever exploiters cant surround it with exploding barrels.
I still dont understand why cant we change Race for our hirelings.

Lets us play Githyanki as racist as they trully are!