You've asked three times about 1099-NEC. Because it's scattered in so many places, you have info that matters, but that info isn't here:

"My client received a 1099NEC for serviing as a trustee to his union."

This is likely what you have:

When the person is not an employee of this entity, not under their direction or control, that makes them an Independent Contractor. This 1099-NEC is filed as Schedule C for the person's 1040. Your person would be a Director, not an Officer, in other words. They don't represent the union or its members; they guide the board for governance of the entity.