We had raised a pega ticket for resolution of this issue and have been able to identify the issue and find a work around.
Below are the details.
Root cause: Pegasystems Bug
Root cause description: A defect in Pegasystems’ code or rules. Issue with the pyHistoryViewType property which is having an empty value. Due to this Audit grid is empty
Solution type: Patch Release
Solution description: This issue is to be addressed in the 8.4.4 patch release. Local change: override the pyArchivedCaseAudit section and change the grid visibility condition from pzShowArchivedHistory && .pyHistoryViewType = 'all' to pzShowArchivedHistory