Wrong origin dialogue during "Pinnacle of its Kind"

After defeating the Formless One in Arlathan, Rook comments about how some demons can project splits of themselves and says "that must be what the one back home in the Vaults is doing".

In this case, Rook is a Shadow Dragon elf, so the vaults are definitely not "home". I assume that the dialogue is only meant to play when Rook has the Mourn Watcher background.