Retrieving permissions configured to folders

Hello,

We have an issue where part of company archives contain folders accessible by other company users by using Archive Explorer. The problematic folders mostly the folders which were migrated by using PST export/import from legacy archiving solution to Enterprise Vault. All of these folders placed under folder named "Old Archive" and, since during the PST import process no corresponding folders and stubs were created in the users mailboxes I don't see any way how to control access to these problematic folders. Is there any way not owner's permissions to archived folders can be retrieved and controled?

Thanks