Hero of Ferelden Codex Error

That does sound like a codex error. I've never heard that elves line from Leliana for any of my playthroughs, and these were with Dwarven and Human Wardens. 

Were any of your playthroughs using an elven Inquisitor? Also are there any other major references later in the game to the warden if they made the ultimate sacrifice (I know there is a whole warden mini-arc if the warden survived the encounter with the archdemon). Although I am 30 hours in I only just arrived to Skyhold, going for completionist playthrough.

Thanks!

Yeah, worry not, I played about 50 hours before seeing it for the first time because I played a mage first, but then decided to go for an archer after doing literally the whole hinterlands, which means I experienced them twice. 30 hours sounds about right if you did the storm coast or  the swamp as well.

Also: Go complete or go home!