Orphan file deletion in Nuxeo

To follow the Bank compliance policy, do not keep the documents of the customer who left the bank.

Since customer wants hard delete instead of soft delete feature provided in Nuxeo.
Customer facing below Issues & Challenges:

There is no report available (before and after deletion) to validate the authenticity of deletion process. This brings the risk of deleting the documents which might be legitimate and wouldn't have deleted by the process

Business Case:
Due to above stated challenges, the orphan deletion process has not been run in PR since customer started using Nuxeo.

There are many binary files from the customers who are already left the bank and retention has also reached for them. Those Binary files are still available in Nuxeo archive making GDPR compliancy issues.
Due to large number of orphan binary files, storage utilization is not optimum and costing unnecessarily.