S3 Export Job Fails on Legal Hold WhatsApp Metadata

Looking for advice on a permission error during bulk exports for legal discovery.

The Create Recording Export Job API returns a 403 Forbidden error.
This happens only when exporting WhatsApp digital channel data with legal hold flags enabled in the EU-West-1 region. Standard voice recordings export fine to our S3 bucket. The payload includes the correct legal_hold metadata tags.

Why is the 403 error triggering specifically for WhatsApp metadata in legal hold jobs?