I get the impression it's part due to a script that used to 'despawn' the bodies of npcs after a time, that's just not firing up after a recent fix , I'm sure Bioware are quite aware of the issue and more than likely with the next fix that script should be corrected..just hang in there

A little ironic for the sith warriors, but if you chose to spare his life..that jedi master who had a vendetta and went a bit loony..Nomen Karr if he's saner..perhaps fighting the eternal empire could be his redemption?