It doesn't come, Grayson's moment of clarity. As much as he wishes that answers will appear at his feet, he knows that nothing is ever that easy. He could just accept that some things are unexplainable and move on with his life knowing he knows nothing. He could, but he won't.
Grayson had never been interested in the paranormal before. Sure, he joked about ghosts because he thought the concept of them was hilarious…but he never actually believed in anything that inconsistent.
He never considered himself a science-minded person, but whole-heartedly believed that the truth is the most important thing in life. Truth is something you pursue, and whether you're a scientist or not, the method is similar.
Grayson had seen Jude transform from a wolf to a human. He had seen an accelerated healing process. These two observations did not give the whole truth.