I see sometimes a player nametag showing up while I’m mining next to me, I hear the sound effect of the watchwork pick and then the player name disappears.
The names when this happens appear at ground level – not at above model high.
It looks like someone teleporting to a node, mining and then teleporting out – sometimes the same name at multiple locations on the same map.
It looks like a hack, but possibly it’s just a display/ server problem.