A device with Special Offers can be jail broken with the current jail break.
It is recommended that you remove Special Offers because that feature can prevent recovering from errors.
You have the original model of the PW-3, there should not be any problems, but there is always a small chance.
So keeping S.O. is your choice.
Since you don't have access to on-line language translation, you might want to wait until a German (I presume) speaking member spots this thread.
Or
do a search for a German translation.
That is: search for the link address:
https://www.mobileread.com/forums/sho...d.php?t=275877
Which should be in the body of any translation.
Russian, Polish, Chinese, Vietnamese, French, Spanish, and others do exist - of varying quality and correctness.
I was sure there was a German translation but I can't find it at the moment.