Do not manufacture an event to fill an evidence request. Confirm that there really were no relevant occurrences and retain the records supporting that conclusion. For departures, that might involve reconciling HR records with the period under review. For incidents, distinguish no reported incidents from a missing incident log or ineffective reporting process. Explain how the control is designed to operate when needed and discuss the appropriate audit approach with the auditor. A tabletop exercise may help evaluate preparedness, but label it as an exercise rather than evidence that a real operational event occurred.
Related: SOC 2 audit and compliance hub.
Further reading: NIST control-assessment guidance.