I have no idea if this is helpful to your research, but a Joseph Kempinger died approx. 23 January 1945 in Milwaukee, Wis. His death notice was published in the local German language paper, possibly the English language Milwaukee Journal or Milwaukee Sentinel too. You can browse their archive by date through Google Historic Newspapers, or Journal Sentinel Archive, start with the Classified section. (I'm not a relative, the local German papers are not online, I don't own the clipping.)
"Milwaukee's German Newspapers; an index of death notices and related items" (1844-1950).
Gary Rebholz, compiler/editor
Indexing Milwaukee's German newspapers continuously since 2007... helping to access our historic immigrant culture.