You didn't remove the user from the BES before uninstalling the BES.
The user's mailbox still has the BES name in it, and Redirector thinks the BES is dealing with the user.
Install BES again, add the user then remove them
Use DBClean to clear the BB info from the user's mailbox. This will clear all BB info from their mailbox, like the BB Auto Signature and filters.
DBClean is technicall only available from Support, but I am sure there are a lot of people that have it somewhere.