well, since the new server is super-powerful, I did some SQL queries to see if I could find the original poll for this thread, based on the hints people have remembered. Sadly, I think it has indeed been overwritten.
For those of you who don't remember the poll bug, we had a problem with the auto-increment key column of the poll table, such that it got set backwards somehow at some point, and for a while, new polls were being created with recycled "unique" IDs. Once this happened, certain other actions could cause one of the two rows with shared (non-)unique IDs to go away, or get updated with the wrong content.