After completing the main story (credits etc) I still have one quest left in the Objectives tab - "The Search for Fish" - "Find ice Worlds for the Mu'Kay in the Wendigo cluster". I have two Mu'Kay Colony Candidate items in the Manifest, however when I talk to the Mu'Kay in their home world they still have the dialogs as before the main quest was completed (e.g. we are in danger help us with this big threat" etc), so the aforementioned quest cannot be completed. I've also noticed the same issue talking to other aliens on their home planets, some of them do not realize that the threat is over, however engaging them in space does trigger different dialogs.