Generally any W-2 has authority to enter into contracts, strictly from the vendor’s POV. As a vendor you don’t need to get your customer’s publicly listed officer or director to sign off on contracts. The W-2 can also be fired for entering their employer into the contract, but that's not (directly) the vendor's problem.

Once a vendor has entered into a contract, that could change - e.g. "any change orders must be approved by $EMPLOYEE_SET".

It's absolutely wild that every W-2 employee can expose their employer to essentially unlimited liability, but AFAIK, that's the truth.