I never noticed before but I just heard a NPC mention a comment about a quest I did and it seems to pertain to the choice I made before abandoning the quest to try the other choice that I went with.
I heard, "All those prisoners at White Rose driven mad. Sometimes you have to weigh the odds.", which sadly doesn't show up in chat with npc dialog enabled to get an exact wording.
I accidentally took the keystone and "drove them all mad" when I first did the quest, so I abandoned and got the quest again and chose the other choice to destroy it, saving the ones who had not gone mad.
The voice dialog would imply that I kept the first choice. The flag updated during the quest and didn't update at the actual quest completion it seems. If it matters, it was the dark elf enchanter in Coldharbour who said the line of dialog.