Where do these names come from? For example https://www.openstreetmap.org/relation/2613078 is neither on Wikipedia https://pl.wikipedia.org/wiki/pl:Borne%20Sulinowo%20(gmina) nor on http://gov.genealogy.net/search/name

Are these nowadays used German names or old German names? If these are names for municipalities used before 1945, they should be in [old_name:de].
I suppose they should be in [old_name:de] because only a few towns in Opolskie voivodships have German names.

If you add a name in another language, you should copy the value of the [name] tag to [name:pl].