It's really common for NPCs to have those sort of non-surname epithets and they'll usually have that version shown overhead in battle instead of their actual surname, even if both are known.
Players don't get that choice, so you actually have to pick between giving your character a proper surname or an epithet as their displayed character name.
I'm still hovering in a state of indecision on actually making my Viera alt, but I'll probably be giving him an epithet as the display name and just have his actual surname in mind without using it. (Especially given how unpronounceable "wesfv" looks.)
