I have just double-checked this quest, in Aureus his dialog there should be an option to say :
-"Let's discuss these expeditions into hostile territory you mentioned."
-"So, about these burial grounds..."
After you have completed the escort, this should fully complete the quest when bringing up the topic to Aureus.
This should do it. I had pretty much the same issue in beta. I didn't know the archaeologist had anything to do with the burial grounds.
