We Already Met

The owner of the voice was none other than Haylee, who emerged from the saferoom the Boyd family leaders escorted her to.

Going back a few minutes ago, after the Boyd family leaders left Haylee in the saferoom, she was supposed to rest. But after sensing the commotion outside, and the arrival of people with two familiar auras she left to take a look. She did not care much about the other aura because it was Osric's but the second aura somewhat gave her a bad feeling— the aura belonging to Tritus, the commander of the Templar Code.

Her bad feeling was soon realized after witnessing the battle between Osric and Tritus from afar. What was more, she could not see through Tritus's soul. It was as if there was a 'void' that prevented her from peaking at his soul.