I highly doubt there is a feature implemented that alters the naming of NPCs depending on the level of your lore skill.
If there is I have not noticed the difference either, while some of my characters have a pretty decent lore skill as well.
Although it is true that you sometimes briefly see them as Gremishka before they are renamed to Small Creature / Humanoid.
The technical reason for that is probably just a minor delay or lagg from the server. And I would guess the reason behind renaming them to begin with may be because they're supposed to represent a variety of generic small creatures / humanoids from folklore, not just Gremishka, even if the mechanics used for it are primarily those of Gremishka NPCs. Only drawing that conclusion based on the fact that certain other areas do correctly refer to them as Gremishka by name, regardless of your lore skill.
That would be my guess and just that, a guess. If there is a renaming server feature related to lore checks it may be buggy.