The fix that is implemented is the same as the fix they did for odin and behemoth, if you want the mob to load you have to stand in the same grid as it(the world is split into an 8yalm x 8yalm grid) if you're standing in the same grid square it will always have display priority. If the mob moves to a different one and disappears all you have to do is follow it to the new grid space. Works every time.