Agents don't know what triggers audits. Those decisions are made at the Service Center, usually after a 1960s algorithm kicks a return out using a 1990s computer.  But then it is reviewed by a human, and sometimes those are detailed-in from local offices (but that reviewer would not end up as auditor).  The agent was, to use the technical term, "pulling your leg."  It was probably your client's neighbor who turned in a whistleblower form because they didn't like all those cars parked in the street for the Tupperware parties.