I triple-checked. I'm still seeding it, and getting a lot of download activity. The numbers of seeds and leechers reported by Azureus (my BitTorrent client) match the numbers reported by Demonoid. When I download the torrent file from Demonoid and attempt to download it, Azureus tells me it's the one I'm already seeding.
Yet it only has one subtitle track, and it appears to go with the commentary. The only subtitle in the Greedo scene says "George Lucas." When that track is off, I get no subtitles at all.
I did burn it onto a notoriously unreliable Memorex DL disc. (I ordered some Verbatim discs from Newegg. These are the ones that everybody recommends. I'm waiting for them to arrive in the mail.) I get some bad glitches. Is it possible for this to cause Greedo's subtitles to disappear?