Franklin stares at the men pointing guns at him for a moment, then with a careful, deliberate motion brings up the arm that he has his pip-boy on, presses the radio button and speaks in a very level tone of voice: "Alice, could you come to the Vault entrance, right now? We seem to have a situation here. Oh, and Elsie, if you want to tell them about your decision, now's the time."
After letting the girls know about the current situation, Franklin throws the Overseer a level, cold look. "I'd be right in calling this a situation, yeah? I don't think you brought the entire security force with you just to make sure no-one sneaks in, or helping carry this stuff since they're all busy pointing guns at us. And if you were worried about contamination or something you'd have brought the Doc with you. Now, call me paranoid, but it looks like you've got ill intentions towards us. It doesn't look like you're trying to kill us, right away that is, so what's your plan?" While talking he takes a half-step back, turns towards the bags of cement, walks over and sits down on one of them, careful to keep the autoaxe hanging from his belt in plain sight.