I am also doing research on the Krohns from Sweden. My great great grandfather's name was Swen N. Krohn. He was born in 1861 in Skone Sweden and immigrated to America in 1881. He settled in Carney Michigan where he had a family with Anna Jacobson. His parents were Nels Krohn and Nila Nellson. He was one of many children including: Nels Gustave Johan Brynolf Sigrid Mathilda Amollia and Emma.
He died in 1947
I was not sure if he was possibly a relative of who you are searching for (They came over at the same time). If any of these names sound familiar please let me know!Thank you!