On one side William's men were tackling with the interrogation at Pike's home to find out about him. Because for some reason his men did not sense any unusual presence there. However, being the creatures of the dark, the men should be able to detect another dark one in the house. But all they could sense was the presence of Pike's father, who was a dhampir.
Pike also had dark blood which he inherited from his father, which should have been picked up by William's men's magic. Because only like could sense like, being a dark creature they should have felt both Pike and his father's presence at home under that one roof. But there was only one such energy. William was trying to find out about Zoravec personally, he could not risk anyone else finding out about him.