An outside POV on John and Rodney is always a treat, and to get such shrewd perceptions on earth-culture was incredibly interesting and well done.
I loved the sense that you know these characters so well that even when they're all feeling basically the same thing--fear, anxiety--you wrote them behaving and reacting so distinctly. I found your Rodney particularly realistic; you didn't try to make his cantankerousness charming (which is fun in many contexts, but would have been a cop out here). My heart was beating faster all through the story...very engaging and enjoyable.