This chapter does not apply to any county having a metropolitan form of government; provided, that each such county shall receive full benefit of all incentives available pursuant to § 6-58-109, and each such county shall escape the sanctions imposed by § 6-58-110; and provided further, that any municipality that lies within a county having a metropolitan form of government and another county must establish an urban growth boundary in conjunction with the county containing the territory that is not within the county having a metropolitan form of government.