I ordered a "misfits" box of plants recently and after a week of traveling at freezing temperatures (around -6 °C, or 20 °F), it arrived today. One of the plants in there is a Dracaena according the EU Plant Passport on the pot; it has comparatively long, wide leaves with yellow stripes and no stem. When it arrived, the earth in the pot was completely frozen, however the leaves appear to be structurally okay.
My main issue with it is that all the leaves either have long brown stripes within them or contain a lot of small brown dots. These spots are entirely within the leave, not "on" them. It seems to be worse closer to the tip of the leaves, i.e. might be older; however, the smaller leaves do carry it as well. (The game with the "misfits" box is that these plants may have been mistreated and aren't "fit" for selling.)
Can someone help me figure out what that is and - given that the pot was frozen - what my best shots are at saving this one?