How does judith loftus figure out hucks disguise?

In the television series "Scandal," Judith Loftus does not figure out Huck's disguise. Rather, it is Mellie Grant who discovers Huck's identity as a B6-13 operative turned Olivia Pope's employee. Mellie recognizes Huck's facial scar, which he had tried to conceal, during a private meeting, leading to her suspicion and eventual confirmation of his true identity.