yeah this or tape pieces of notebook paper to the inside..make sure they have a matt finish and that its not a glossy finish..how soon are the lights coming?Painting inside of box white would help light intensity, and you'll need some air movement in the box. Plants need CO2 and in that small space, it will quickly exhaust available CO2 without some movement. Temp regulation and humidity will be an ongoing challenge.
thats a bit of an over the top reaction... should really have let them know... but what twat... can they be saved? hope they can.. if you have to go out door. you ca get acluch... about 4 pound from gro shop... stop thr frost....