So, about this "Wall of Mirrors" that got mentioned several times in the thread.

From this fan wiki:
The novel Crucible: The Trial of Cyric the Mad states that Kelemvor also replaced the Wall of the Faithless with a mirrored wall that showed the false and the faithless their reflections in such a way as to reveal the follies and life choices that led them to be sent to his realm. However, the more recent Sword Coast Adventurer's Guide sourcebook still describes faithless souls being mortared into the Wall for eternity.
Could it be that WotC simply fixed a continuity error? Or is the wiki wrong because the Wall of Mirrors was one of the changes Kelemvor had to undo?