it seems the OAI-PMH in DSpace 4.1 doesn't display deleted items correctly (or at all).
The repository is set to persistently keep track of deleted records by default. That means even the withdrawn items should appear in some of the listings (identifiers/records). They should have header with status deleted.
I'm not able to obtain the deleted records even with GetRecord (all I'm seeing is '<error code="idDoesNotExist">The given id does not exist</error>').
It seems the withdrawn items are not even taken into account when you do bin/dspace oai import -c (judging by the reported Total).