Former FBI agent Scott Curtis explained why the new images of a potential subject in the disappearance of Savannah Guthrie's mom, Nancy Guthrie, could help expedite the case. "I don't think they were holding on to these [images] for any significant length of time because of the value of these," Curtis exclusively tells Us Weekly. "As we've seen in a lot of investigations over the last 10 to 15 years, getting a video or still photograph of a potential subject significantly accelerates the pace of the investigation.