@Bernhard On this point I would side Bohemian or Moravian ancestry because “Tuhý” is a surname describing feature of given person (tough or thug if you want) in Czech language. Description of given feature in Silesian language would be “Twardy” – more similar to Polish language than to Czech. Also letter “H” is quite rare in Silesian, you can mostly see “G” in Silesian where Czech uses “H” for instance: EN-His, CZ-Jeho, SI-Jego.