The policy migration tool doesn't have a lot of debugging associated with it.
All it's doing is running some embedded SQL scripts, picking the script appropriate for your needs (or that you specify via command line).
But, you can get some info by piping output to a text file, e.g:
If you have already run the tool then the tool is not expected to run again, rather, it'll quit intentionally.
To reset your database to allow the tool to run again, you have to remove the appropriate VSE extension and add it again (this loses any VSE policies for that version, but also removes a "MigrationHappened" flag the tool is checking for).
Also, I don't think we can migrate 8.0 to 8.8 policies; just 8.5i or 8.7i to 8.8.