"[T]he determination of whether section 162(m)(6) applies to a risk-bearing entity providing services to Medicaid recipients requires application of the definitions of health insurance issuer and health insurance coverage to those arrangements.... Although section 162(m)(6) is a provision that is not part of HIPAA but rather is a provision of the Internal Revenue Code over which the Treasury Department and the IRS have sole jurisdiction, the failure to coordinate the definition [with other agencies] raises significant litigation hazards with respect to enforcement of the application of the deduction limitation to these entities.... Accordingly, we advise that for purposes of section 162(m)(6) the type of organizations identified in the recently issued CCAs not be identified as health insurance issuers and that the arrangements not be treated as providing health insurance coverage until such time as that coordination has been completed, and that any such treatment depend on the result of such coordination."