In 1942 Matuschka became an administrative economic adviser in annexed Regierungsbezirk Kattowitz. He was supposed to become the head of administration of Silesia by the plotters of 20 July 1944 and was arrested by the Gestapo after the plot failed. Matuschka was sentenced to death by the Volksgerichtshof on 14 September 1944 and executed the same day in Plötzensee prison next to Heinrich Graf zu Dohna-Schlobitten, Hermann Josef Wehrle and Nikolaus von Üxküll-Gyllenband.