There is no need to create the folders before performing a Public Folder migration unless migrating more than 20 GB of data to Exchange Online. In that case, BitTitan support will need to provide scripts to create the IPF.
Note Folders and Additional Public Folder Mailboxes Before Migrating
MigrationWiz will create all folders from the root to the folder being migrated. However, only the migrated folder will have proper permissions set and will be mail-enabled (if appropriate).
Source and Destination Folder types must Match
This means that if you are migrating a Contact or Calendar folder, the destination folder must be created as a Contact or Calendar folder.
Folders other than IPF
Note (Email) folders can only be created correctly through EWS, which is what MigrationWiz uses for migrating public folders. If the folder is not of the correct type, no items will be migrated into it (e.g., mail items cannot go into a Contacts folder, and vice versa).