So I managed to figure it out I think. I was using "true" instead of "success" as the state designation in Dialogue System. I forgot the change in lingo between QM and DS. Quests states reverting to inactive and registering the quest again is the result of an invalid state apparently.
Just to confirm another behavior I found while debugging. If you use SetQuestState, then it set the overall quest state as success but will not automatically progress any of the nodes? That would have to be done separately? Makes sense if so, I just want to confirm.
Current Tracked Quest
Re: Current Tracked Quest
Yes, that's correct. Take for example a quest that has two paths to success. When the main quest state is successful, you'll still only want one path's nodes to be true so that the journal text only shows those nodes as having been completed.