This is expected behavior in IIQ. IntegrationConfig / AbstractIntegrationExecutor is only invoked for LCM access requests, not for certification‑driven revocations.
During certifications, IdentityIQ bypasses the provisioning engine entirely and generates manual revocation work items directly, which is why your executor is never instantiated and no ProvisioningPlan is created.
I would try below:
Remove the IntegrationConfig for this use case and implement a CertificationPhaseChange Rule instead. That is the supported extension point to intercept revocations, split them per application, and route manual revocation work items to the correct application-level revokers.
Official References:
Certification revocations bypass provisioning integrations
SailPoint docs confirm that certification remediation does not use workflows or provisioning integrations and is handled by the Certification / Remediation Manager instead.
Processing Provisioning Requests - SailPoint IdentityIQ
IntegrationConfig scope is LCM provisioning only
IntegrationConfig - IdentityIQ (IIQ) / IIQ Discussion and Questions - SailPoint Developer Community