"Local Company' usually means an organization not in Confederate service operating under the authority of the governor or a state official designated by the governor or the state legislature. Members would not have been subject to conscription and must have had some kind of legal exemption from military service. Members were not paid and did not receive arms, uniforms, equipment or supplies of any kind from Confederate sources.
During the summer of 1861 the Confederate Congress authories Local Defense companies which met the conditions just described. However, the military service law of April 16, 1862, removed most men between the ages of 18 and 35 from these companies. Most ceased to exist afterwards. Local Defense companies that organized after April of 1862 consisted largely of men exempt from service because they had furnished substitutes for the army.
Since Capt. Cameron's name doesn't appear on the roll of a Local Defense company, I must assume that he was an officer of a 'home guard' unit which organized under state authority. Records of state commands should be available at the Georgia State Archives.