Yes, he was the first SDA coming back to Europe ! In Swizerland he at first converted the S.Crischona - alumni Erzberger, then active in ministering penitentiaries - and Erzbergers SDA mission then covered a large area in Swizerland and Germany around the Rhine. - - Czechowski was in Italy, down the Balkan, Hungary - and finally died in Vienna. (on his way to Poland ?) , most probably on meningeal tuberculosis.
Maybe I get the photos of the clinic here in Vienna he was delivered to at. first and sketches of the asylum , where he died and show them here in the NET. Anyhow, are you visiting Vienna once ? I could show you around the places that were the last fo him living on our earth. Some of his last steps you could follow. His death is documented in the archives of “Evangelische Stadtkirche” , yet we did not find where he was laid to rest.