On the NMLS website for WI I read through the requirement checklist for company and branch and individual. Doesn't seem as though mortgage lenders working for a financial institution are required to register. Or have I missed something?

Wisconsin Mortgage Originator Licensing Information

I would agree with you. Mortgage lenders do not need the WI state license provided:
*They work for a federally regulated depository institution, AND
*Maintain federal registration on the NMLS

So, even though the state level isn't required for our individual lenders, federal registration is.