"While the FAQs provide much needed clarity on the subject, ... employers must be mindful of other laws and guidance ... For example, any wellness program must still comply with other federal nondiscrimination laws. Additionally, the wellness program must otherwise be 'voluntary.' That is, an employer is prohibited from: [1] requiring employees to participate in any health care plan, [2] denying coverage from any plan, or [3] taking any adverse action against any employee who declines participation in any medical examination or wellness program."