In the scene where Special Agent Gibbs is interviewing the female college student in her dorm room, the young woman shows Gibbs a picture of her boyfriend in Bahrain. The picture shows a sailor, in uniform, in front of a mosque. Military members are not allowed to go off base in their uniforms in Bahrain and there are no mosques on the base.
Ziva tells Sarah that she isn't under arrest, but that she does have to come with them for questioning, wording it like she has no choice in the matter. However law enforcement cannot force a person to go with them for questioning if they aren't under arrest, if Sarah did indeed have no choice but to go with Tony and Ziva that would mean she is under arrest, even if she wasn't in handcuffs.
When McGee creates the map on his computer to retrace his sister's path from the night before, the icon for his apartment is located inside of Arlington National Cemetery.