How to track form submissions
Start by recording the handoff from the form service.
Ask which server receives the form, which fields it sends, and which system should receive the result. Keep credentials on the server, never in browser HTML.
Submit an event with a stable source reference and Idempotency-Key. Save the returned event ID. Use a clearly marked test request before forwarding real customer information.
When a request is missing, follow receipt, validation and delivery in order. A failure before Data-Line receives anything must be investigated at the form source.