That's not what the quest "lock" does, it simply makes the quest text fixated so you don't accidentally display the information of another quest by hovering your cursor over it (only noticeable on desktop).
If you have version 0.64 then you could try the Discord group, it has channels for frequent mistakes and common misconceptions and people there are quick to answer your questions.
Anyway, which ruin acolyte did you help? The one that counts towards quest completion is being held captive by the warriors. You can confront them late in the afternoon I believe.