I really wish Larian wasn't so secretive about the Durge being a what it is, had I'd known on release day I would have made it my first playthrough. But instead I got it spoiled for me in act 3 because Larian just put it in the game for literally no reason.
If all you saw was
that body and used speak with the dead on it
I really wouldn't worry about it...it doesn't tell you much about the origin at all and what it does tell you is nothing that many hadn't figured out by simply being familiar with the lore of the dead three and the evens of BG1 and BG2.
