IIUC allowBulkEdit property is used in context of WCM (foundation page component) and not applicable for DAM metadata editor. Following metadata schema should be used to customise the metadata editor fields.https://docs.adobe.com/docs/en/aem/6-1/administer/content/assets/metadata-schemas.html

Yes it should work. Property dam:status is on metadata node, hencepath = /content/dam(/.*)/jcr:content/metadatanodeType = nt:unstructuredCondition: dam:status==approved (without quotes)