Knowing that one of Nancy and Terry is innoccent and one is criminal, look at Olive’s clue about Sofia. Sofia has three confirmed innocent neighbors and one that has not been determined, for a total of four. This means no one else can have more than three innocent neighbors.
Since rows one and five together have a total of two innocents per Zach’s clue, one of either Alice or Betty must be innocent. Floyd has two confirmed innocent neighbors, and one additional undetermined (Alice/Betty), for a total of three. This means Isaac must be a criminal, otherwise Olive’s clue would be violated.
Edit: easier proof - Katie is already neighboring three innocents, she cannot have a fourth innocent neighbor. Therefore Isaac must be a criminal.
Next steps
Knowing that one of Nancy and Terry is innoccent and one is criminal, look at Olive’s clue about Sofia. Sofia has three confirmed innocent neighbors and one that has not been determined, for a total of four. This means no one else can have more than three innocent neighbors.
Since rows one and five together have a total of two innocents per Zach’s clue, one of either Alice or Betty must be innocent. Floyd has two confirmed innocent neighbors, and one additional undetermined (Alice/Betty), for a total of three. This means Isaac must be a criminal, otherwise Olive’s clue would be violated.
Edit: easier proof - Katie is already neighboring three innocents, she cannot have a fourth innocent neighbor. Therefore Isaac must be a criminal.