Yes, I interrogated the vampire in his secret lair behind the wine seller basement, I spoke with him about George. And yes, Mardaneus still in Aleroth, does he ever move out of the healer city ... eh town? He didn't want to go with the other healers, as far as I recall, that's why I was headed to Aleroth to speak with him there. But the only options are to get healed, or to speak about the Source. Btw I healed both the soldiers early on with that magic mirror duplication method of the last healer gem. Doesn't that solve/close the Source quest? Or am I mistaken? Perhaps the poor Mardaneus is still suffering from the necromancer's curse, or something.
Well I'm far from the endgame yet (still have to go to play Janus'es lackey), so I'll have to get used to the broken questlog for quite some time, I guess.