This doesn't quite fit, but it caught my eye.
In the 1900 census for Highland, Lincoln county, South Dakota, there is a family of Even and Inger Fossum. They have a servant living with them named Hans K. Vatne. Hans was born Apr 1874 and it says he arrived in Norway in 1899. This would be too late for "Hans Foss", but the date could be wrong.
According to passenger lists, Hans K. Vatne left from Stavanger, arriving in New York on 5 Mar 1898. His destination was Canton, South Dakota, to his cousin L. Ostraat.
I don't find Hans Vatne after the 1900 census, but it appears he traveled back to Norway in December of 1898.