on the jailbreak thread it says:
- for Kindle Touch 5.0.x use data.tar.gz
- for others (ie Kindle Touch(5.1.x)and Paperwhite(5.2.x) ) use data.stgz
Hence you should use the data.sgtz file for Paperwhite. You should have a "you are jailbroken" file in your Kindle after using it.