What happened to the submarine the two bad guys came in? They weren't shown doing anything with it before stealing the underwater prober, so shouldn't it have still been floating offshore when Dr. Quest and Hadji returned to the island? Or did they just not anchor it and let it drift away?
Why did Dr. Quest stop the underwater prober after the minisub attack while they were escaping? Shouldn't they have kept on going? I know the real reason is so that the bad guys could attach the mine to the prober, but there's no In-Universe reason given.
"The Quetong Missile Mystery"
After Race Bannon takes out one of the guards with a sleeper hold and dumps him in the water, he answers a radio call to Post #5 (apparently the call sign of the guard he just disposed of). Later on as the Quest team escapes, Post #4 calls Post #5, and the Post #5 guard is lying down in his observation post holding his head. Shouldn't he be in the water where Race left him?
"The Sea Haunt"
After the monster damaged the Quests' plane, why didn't they try to use the plane's radio to call for help?