I know someone whose last name is Koch pronounced “cook.”
I used to know someone who last name was Kuntz pronounced “coon-yetz.”
Really.
There are many family names that have the word Koch in them including one well known ex mayor of New York City. I had reason to look up lineage of the name. There were many Koch——s that had roots in western Germany that migrated to the USA. I think the Koch brothers roots are in NW Europe. This is a very educated and talented family.