what i would suggest is next time, when you export the PST, make a copy of it before doing anything else
to be honest i havent heard of an export causing duplicates and moved items
though typically what happens in EV2007 and such is when you do an export its going to export out to its original location
so if you had a bunch of items in \inbox and then you archived the items and moved the shortcuts to all sorts of different folders, when you do the export, it will export them to their original location in the PST. in this scenario even though the shortcuts are in \inbox\myfolder1 and \inbox\myfolder2, they would all go back to the inbox
In EV8 it does remedy this if you have the update shortcut location turned on in the policy to allow the archive to be updated to where ever you moved the shortcut to
https://www.linkedin.com/in/alex-allen-turl-07370146