The Integration ID field is not currently included in the Gradebook export file. It can be displayed within the UI as a "Secondary info" field within the New Gradebook.
The omission of the Integration ID field in the export file can be an issue if this field houses a key value that is used to pass grades from Canvas to other systems (e.g. student number). This applies to use cases where instructors or course staff are required to export and import student marks manually.
This idea is to modify the Gradebook export file format to include the Integration ID field.