Sounds like a goofy design, the only reason you'd do something like that was because a world voltage input SMPS didn't exist.
Is the 300 volts used for some other purpose like the monitor? If not I'd replace the 2 modules with a single 15V 200W SMPS such as the Meanwell SP-240-15, assuming it would fit in the serivce monitor, never seen the inside of one.
