Apparently you have seen the 1910 US Census, which lists the same information you already know.
www.ancestry.com 1910 US Census Name:J M Heimberger Age in 1910:26 Estimated Birth Year:1883 Home in 1910:TWP 140 RANGE 90, MORTON, North Dakota Race:White Gender:Male Series:T624 Roll:1144 Part:2 Page:333A Year:1910
Heritage Quest - 1910 Census image 1910>NORTH DAKOTA>MORTON>TWP 140 RANGE 90 Series: T624Roll: 1144Page: 333 SurnameGivenNameAgeSexRaceBirthplaceStateCountyLocationYear
HEIMBERGERJ M26MWGERMNDMORTONTWP 140 RANGE 901910 Head, age 26; occ:Hotel Manager Kathie (sic), Wife, age 27, married 5 years; children, this mother: 2, 2 living. George, 4, Son, b. N Dakota Oscar, 2, Son, b. N Dakota
http://www.rootsweb.com/~flbrowar/howto.htmlhttp://www.rootsweb.com/~flbrowar/howto.html Above web site has instructions for obtaining death certificate (ask for cause of death) and Probate Court proceedings (estate settlement).You might ask if possible to locate record of possible remarriage of "Kathie" Heimberger.
Was unable to find subject or his widow (if not remarried) in Florida Death Index, or the SSDI.Did not find the family in 1920 US Census.Possibly spelling of surname was different.
If the story about the place & year of killings is factual, as opposed to rumor, there must have been newspaper articles --- difficult to locate, even with exact date of incident.The residence in Fort Lauderdale could be checked in old city directories, which were printed in numerous sections according to area, such as "Pompano Beach", Deerfield Beach, etc.Occupation is oftentimes listed."Ask a Librarian", by finding Broward County Library web site on Internet.
The "Heimberger" surname appears in SSDI, FLDI and current phone listings in Palm Beach county, and other FL counties.
Wish you luck, and wonder why you want to know, since there are no descendants.