Ken, I have checked the Illinois Secty of State site. It lists deaths 1916-1950 and pre-1916 and marriages 1763-1900.
I found no listing in any for the name Rölz. Nor did I find any deaths for Stowasser or Stovasser in 1763-1900, however, there was a death for E. Dorothy Stowasser on 19 February 1933 in Calumet City, IL cert. # 5130012.
These are the only similar marriage items I found under any of the mentioned names:
Sophie Rozlow and Johann Witthoeft on 26 November 1876 in Cook County and Joseph Rolzine and Franciska Szymanowska on 10 September 1888 in Cook County.
Have a very Happy New Year.