### Check for existing issues

- [x] I searched open and closed issues before filing - [x] [#28562](https://github.com/BerriAI/litellm/issues/28562) is related to passthrough call ID correlation but does not cover primary-key collisions or dropped rows

### What happened?

The proxy accepts a caller-provided `x-litellm-call-id` and uses it as the fallback `LiteLLM_SpendLogs.request_id` whenever the response has no provider ID, including failure and passthrough-style logging paths

`LiteLLM_SpendLogs.request_id` is the table primary key. Spend-log batches are inserted with `create_many(..., skip_duplicates=True)`, so a repeated call ID does not produce an error or a second row. It is silently skipped

A client can therefore reuse one header value across many requests and retain only the first per-request spend-log row. Aggregate key, user, and team spend updates use separate queues, so this does not directly bypass aggregate accounting, but it does make the request audit trail, per-request cost lookup, and analytics incomplete

The trace identifier and durable spend-log identifier currently have incompatible trust and uniqueness requirements. The trace ID is intentionally client-con…