Quality Evaluation API returning 403 when triggered via ServiceNow Data Action

Why does the Genesys Cloud Quality Evaluation API returns a 403 Forbidden when called from a ServiceNow Data Action, despite using a valid OAuth2 token? The integration works fine for standard incident creation but fails specifically on the /api/v2/quality/evaluations endpoint.

{
 "code": "forbidden",
 "message": "User does not have permission to perform this action"
}

Checked the role assignments and the service account has the quality-evaluation:read scope.