Let's say Maxwell asks Marlo - or whoever comes to recruit them - point blank what's stopping someone from just squirreling one of these caskets away and using the power for their own Pursuit of Science, what would they tell him?

He has a naturally disarming personality and would play it off like he's concerned; even so, he knows it's sus to ask and that won't really stop him.

(but he's the type to try to steal it unless someone tells him it's hard, y'see...)