1. PCI Security Standards Council, Assessor Quality Management (AQM) Program Guide, Version 2.1 (October 2022):
Page 5, Introduction: "The PCI SSC Assessor Quality Management (AQM) Program defines the quality-assurance requirements and activities for all PCI SSC Assessor Companies..."
Page 6, Section "AQM Program Scope": Explicitly lists the "Card Production Security Assessor (CPSA) Program" as being within the scope of the AQM Program.
2. PCI Security Standards Council, Card Production Security Assessor (CPSA) Program Guide, Version 3.0 (June 2022):
Page 11, Section 3.5 "Quality Assurance": "PCI SSC maintains a quality-assurance program to ensure that all program participants perform their duties in a professional manner and in accordance with the requirements of the CPSA Program. PCI SSC performs an annual review of each CPSA Company..." This section directly states that the PCI SSC performs the quality assurance reviews.