The employer mandate does not go into effect until at least 2015, so employers are not obligated to provide health care under federal law. Since health care is voluntary, the GA Company is not obligated by federal law to do anything. Whether the GA Company has an implied or actual contract with its employees is a different matter (the Company may have agreed as part of the terms of employment to provide health care). Often health care insurance is purchased based upon locality, but often it is purchased nationally or over many states. It would be very unusual for GA to require the employer to purchase health care plan benefits by domicile.
The employer mandate portion of the ACA has been postponed until 2015. Accordingly, employers are not required to offer coverage to its employees yet. Even in 2015, whether an employer must offer health coverage or face a penalty will depend on whether the employer is considered a "large employer."
Often insurance contracts are written in the state in which the employer is located. However, there are many other instances, particularly with national employers that have policies written in several different states or in one state that covers all employees regardless of where the employee is domiciled or where the company is headquartered. Some states do, however, have special State Insurance Commissioner rules,addressing this issue that could apply to insurance in that state.