Bulk Export 400 Error: Invalid Metadata Filter for Legal Hold

Why does the Bulk Export API returns a 400 Bad Request when filtering for specific legal hold metadata on digital channels? The standard export for voice calls works perfectly, but chat transcripts fail immediately upon job creation.

We are using the Genesys Cloud Python SDK v2.34.0. The request targets the analytics/reporting:export scope. The error message is generic, citing a ‘validation error in filter definition’.

Here is the payload structure:

{
 "view": {
 "id": "analytics/conversations/v2",
 "filters": [
 {
 "dimension": "wrapupcode",
 "operator": "eq",
 "value": "LegalHoldActive"
 },
 {
 "dimension": "type",
 "operator": "eq",
 "value": "digital"
 }
 ]
 },
 "schedule": {
 "type": "oneTime"
 }
}

The timezone is Europe/London. The view ID is correct and accessible via the UI. However, adding the type filter for digital channels triggers the 400 response. Voice filters work fine. Is there a known limitation with digital channel metadata in the bulk export view definition?