From Halopedia, the Halo wiki
The unidentified Kaidon was part of an excavation team sent to Madrigal to excavate a Forerunner artifact. He later witnessed the Master Chief activate the artifact prompting him to escape in a nearby Is'belox-pattern Banshee. He later went before the Hierarchs and Makee and told them what he saw when the Master Chief activated the artifact.
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