This checklist provides a structured assessment instrument for external auditors, Joint Commission surveyors, and regulatory bodies evaluating AI-supported clinical governance architectures. It operationalizes substrate-layer structural signal detection across ten governance domains: oversight structure and accountability, model lifecycle and vendor management, clinical workflow integrity, assumption lifecycle management, boundary deformation and shadow governance detection, cross-substratepropagation controls, escalation playbooks and severity tiers, regulatory alignment (OCR/ONC/CMS), documentation and audit trail completeness, and final auditor determination. Each domain specifies observable indicators, pass/partial/fail criteria, severity tier implications if failed, and required evidence artifacts. The instrument is designed to detect structural failures—governance conditions that precede incidents—rather than relying exclusively on incident-based assessment.