Did you notice the immigration year for Frank as listed on the 1920 Great Falls MT census was 1910?
Suspects arriving at the Port of Galveston
NAME DATE of ARR. DOB RACE SHIP
Franz Scherer 28 Sep 1910 1885 Male Bremen, Bohemia Koln
However he arriving with a wife, Anna and son Franz
What evidence do you have that Frank arrived 1901? Or is this simply family oral history?
1920 Great Falls MT census
Frank Sharar 35 immigrated 1910 born Austria ethnicity German
Matilda Sharar 25
Mary Sharar 5
Frank Sharar 3
Adolph Sharar 30 brother immigrated 1911
The so-called Spanish Influenza (actually spread from a Kansas military base) was 1918-1919. While there was influenza in 1916 it was described as mild.http://1918.pandemicflu.gov/