This as far as I know is ONLY for the US Verizon and US ATT versions, due to our locked bootloaders. If you have a German version I am guessing it is an international version. I think you should use CF Auto root to root your version as you do not have a locked bootloader.
Now if you are soft bricked you will need to find the firmware version for your phone to flash and get you back to stock. Then check the international forum to make sure CF Auto root will work for your phone and its firmware
This is probably the case, as this rooting method only works on the Qualcomm chipset. The international version use a a different chipset.
No your device should not be perma-bricked you will need to purchase a USB jig for download mode. They can be purchased on eBay.
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