In case it's helpful to Walz family research, there was a wedding anniv. photo and bio. for a Mr. & Mrs. Michael Walz published in local German papers; death notices for Michael shortly after, and a brief clipping for the marriage you referenced: Tillie Walz & William Nonnenprediger. Some other surnames referenced with Walz include Mass and Herman.
"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