Kind of a shreddy thread, but who are the man and woman sitting with Townes van Zandt in this video of Pancho and Lefty?

I ask because of the approving little half-smile and nod the man gives at some of Zandt's slides and chords - he looks like the teacher noting that a prize pupil has done well - and the woman, also proud, is deferring to the man in a way that suggests the same.