The game Otis and friend play (Settlers of Catan) requires *three* people minimum - it is impractical to play with only two as they do.
This episode begins with Gabriela Dawson calmly taking an exam and watching Rebecca Jones cheat. In the Chicago universe, her nephew Diego Dawson was kidnapped at the end of "Chicago PD; Stepping Stone" which aired 6 days prior to this episode. However, there is no mention in this episode about that incident and it is inconceivable that a family member of a kidnapped child would be in a class or behaving as calmly as this character is given the circumstances.