This is a different situation though, as stand alones KOTOR 1 dark side works. KOTOR 2 dark side works (they even managed to make it fit with KOTOR 1 dark side) And the same for Force Unleashed. But if in a single game, there was to be a contradiction in storyline i.e LS BH kills Darth Tormen, Darth Tormen pops up on the Dark Council, the storyline would become fractured. While DS makes more sense you have to accomadate all players, especially role players. The only way of getting around this is having him appear as alive in EU works, or having him appear in the game, but not in the BH storyline. Both still don't fully solve the problem. The second one especially as I feel the storyline are to become more merged together.
While Tormen is a good candidate, there are too many obstacles to navigate. I would choose someone else if I were them. But I'm not, so I can't say for sure.
They can use the Lord Draahg method, our Sith Inquisitor/Warrior also came back from near death and the enemy thought we were dead. It's not a big deal and the Empire already lost many cool Sith.