After the import is complete, there's a folder named after the old email address with a subfodler inside it named "Top of Information Store" and in there is where all the mail is. Now I'm getting tickets raised by users asking where their mail is. And no, telling them it's in that folder does not help. It has to be in the correct place so now I have to remote into people's mahcines and move the mail for them.
I've read several places about making sure that TargetRootFolder is / and I did make sure that was the case but it seems to have ignored it. Here's basically what I used: