Compare successful controls before inferring missing SIP headers

Compare a rejected transfer with a successful transfer before interpreting an empty normalized call-record field as a missing SIP header. If the field is empty in both, that observation does not discriminate between header loss and another authorization failure. Correlate each outbound attempt with its own active inbound leg, retain the rejected primary separately from any successful fallback, and obtain the actual signaling before changing header propagation. This control does not prove that the successful call carried the header; it establishes the limit of the normalized field as diagnostic evidence.

Applies when: A transfer investigation attributes caller-identity rejection to an empty provider call-record field. Keywords: SIP transfer caller identity diversion normalized records successful control rejection