94th Coast Artillery (Antiaircraft) sailed from New York to Australia via the Atlantic and Indian Oceans, February-March 1942. The regiment was credited with participating in the Papua Campaign. Under the Coast Artillery Reorganization of 1943, the regiment was reorganized and redesignated thusly:
Regimental Headquarters & Headquarters Battery became Headquarters & Headquarters Battery, 94th Antiaircraft Artillery Group
First Battalion became 743d Antiaircraft Artillery (Gun) Battalion. Campaign credits: East Indies, Papua & New Guinea.
Second Battalion became 209th Antiaircraft Artillery (Automatic Weapons) Battalion. Campaign credits: Papua & Luzon.
Third Battalion became 236th Antiaircraft Artillery (Searchlight) Battalion. Campaign credits: Papua, New Guinea, Bismarck Archipelago, Leyte, Luzon and Southern Philippines.
Battery A was an element of the regiment's 1st Battalion. If he continued with the battery subsequent to reorganization, he would have been a member of Battery A, 743d Antiaircraft Artillery (Gun) Battalion.
Milne Bay is in Papua New Guinea. No idea of what or where "Waggs Waggs Island" might be.