Thanks Seeking Wing, though I’m afraid that page was discovered a while back; I managed to find it in a Google search that had nothing to do with Panzer Dragoon, and I posted about it shortly after. Thanks for keeping an eye out, though.
Oddly enough, although Sega of America’s PDO site has been offline for ages, they seem to have kept the Flash game online:
Quite a lot of official PDO content can still be found on Sega of America’s PR servers, too. As these are original press release images and things though, most of the filesizes are relatively huge: