event and timestamp attributes are normalized where possible; other attributes are passed through as-is. Not every value in event has a normalized name — container movement events are usually normalized, but exceptions occur.
The response includes an original_event field with the raw carrier event name, which is not present on transport_events.
raw_events vs transport_events
Use
transport_events for past milestones. Use raw_events only when you need the carrier’s original event name or estimated future events that are not yet delivered as transport events.