HDL loading error LegalEmployerName

Summary:

I'm trying to test the bulk load of a HDL file but getting the below error:
The METADATA line can't be processed because the LegalEmployerName attribute is unknown for V2 version of the Worker business object.

I can see lots of other questions for similar errors in the community, but none for this BO.

I checked the business objects and from what I can see it is a correct and valid BO.

Has anyone else come across this? If so, how did you resolve?

Content (please ensure you mask any confidential information):

This is the data I'm trying to load, anonymised -