I'm guessing that they had the same composer. Both companies are in Taiwan, this composer wouldn't be the first to write for several different companies, and there are bootlegs that either remix or write new songs for bootleg ports, so I guess the guy re-used an old song from his Sachen days. Speaking of which, I know Yishen Liao re-used some songs for both Monopoly Madness (Vast Fame, GBC) and Pocket Monsters 2 (DVS Electronic?, MD).