The corpse seems to land on the "floating bottom fake-ground" of the zone, directly below where you fell and died. I have managed to retrieve such a corpse in Stratos by targetting it (using something like necromantic divining device, or another groupmember in group who can target the corpse in the group window) then falling down again where I originally fell down and spamming my /corpsedrag key. When the person who is spamming /corpsedrag pops up back at the zone-in of Stratos, the corpse has come along with them and can now be rezzed.
If I'm in group and the rest of the group is in the zone, just grab the corpse and rez them there. Saves running back and forth and a summon-stone. If I'm alone, I'll anyway probably want to go back to doing whatever I was doing in the zone so I'll be running back to the zone. Just jump off to grab corpse and rez in zone. It's primarily the convenience factor and avoiding paying for a summon-stone.
Happened again today. Could be called to corpse by druid, but got ne rezz from cleric merc. And corpse could not be dragged. But rezz by druid was possible, lol ! This sounds like a really annyoing bug, maybe daybreak can look into it?