Through OSHA (Occupational Safety and Health Administration). I.E. viewing unvaxxed employees as making the workplace unsafe. Businesses that don't comply will be fined.
Patriots should have fought hard against OSHA in the first place, because the whole concept violates the Constitution directly.
"A senior administration official estimated that this new OSHA requirement will cover about 80 million workers and businesses that do not comply with the agency’s rule can face substantial fees"
I hope so. I'm not a lawyer, but doing it through OSHA and workplace safety is using a firmly established violation of the Constitution which will make it more difficult.