As a proud owner (but late-to-the-party player) of Space Crusade, I see the great mystery in English of what a "Devastator" is meant to be from the Alien Event Card of the "Ork Mekaniak."
Using autotranslate on parts of the German Edition (StarQuest) I am inclined to believe it was intended to be a Plasma Gun so that's how I'm going to treat it when I play (we hope to play most Friday afternoons starting in December). Any problems with this idea?
I also like Gold Bearer's comment here
I realize you could also make it a "Flamer" but since this never appears in the board game I'd treat it as a synonym for the same gun (I haven't seen how the "flamer" functions in Voyage Beyond computer game yet) as the old name for the Plasma Gun (called the Black-hole-blaster in the German version!).