Hotchner misquotes the opening verse of Philip Larkin's "This Be The Verse." The original uses the f-bomb rather than "mess".
Spencer always refuses to shake hands, often quoting "the number of pathogens" transferred by hand-to-hand contact, yet he sits on an unkempt bed in a filthy apartment, and remarks about the art on the walls (painted with human feces). It is accepted and known that Reid is germaphobic; Matthew Gray Gubler even tweeted to confirm this. However, Reid frequently does things that he is not comfortable with for the sake of his job, and because he is aware of how microexpressions are perceived, he would have forced himself to appear relaxed in order to get Bill Robbins to stay relaxed and engaged.
There is no train station in Glendale, AZ, but there is one in Glendale, CA. By reviewing images on Google, one can clearly tell they filmed in California, not AZ.