I agree that it looks messy and unprofessional. If my lab would look anything like it, I'd be fired on the spot.
My main concern wouldn't be the distance to a pressurized container or any other particularity but rather the entire setup. This is supposed to be a nuclear reactor where nobody really understands how it works and how it behaves. Would anybody here simply span such a thing in a vice, pop a thermometer in, don't attach any aparent means of cooling and see how ever many kW it may or may not spit out? And stand right next to it, totally relaxed without the slightest safety measure - not even protective glasses or gloves or a glass wall or somebody with a fire extinguisher or, well, anything? If this is anything other than their very first experiments from a year or so ago, then at least my confidence in Defkalion would take somewhat of a plunge.