Public folder migration: Whats wrong with this Folder to mailbox file?

Hi,

This is my Folder to Mailbox file, migrating public folders from 2010 to 2013:

"FolderPath","TargetMailbox""\","Hierarchy-PF""\IPM_SUBTREE\Office1","Office1-PF""\IPM_SUBTREE\Office2","Office2-PF""\IPM_SUBTREE\Office3","Office3-PF""\IPM_SUBTREE\Office4","Office4-PF"

All these PF mailboxes live in a dedicated database. But only the mailbox DB containing Hierarchy-PF is growing and my initial migration (New-PublicFolderMigrationRequest / Step 5 in the technet article) is over 50% percent complete. This mailbox is going to be over 300GB big and I gather the limit is 100GB, I'm sure that can be exceeded without problems, but I had several different reasons splitting the mailboxes and data the way I wanted above. 

Questions:

1. How do I achieve the end result I want? Do I need to add a \ to the end of the office1-5 ipm_subtree perhaps?

2. Is there any problem with me stopping the existing migration, deleting that request/mailbox/DB and starting over?

Thanks.