Okay, so it was an issue of lack of available documentation in the timeframe in which the organizer had to make a decision. They aren't allowed to deny an elgible couple, and you can always DQ someone after the fact, but you can't retroactively put them back into an event.
The answer seems not to be to change the rules, but rather to do something like requiring all sanctioned competitions to submit an official list of placings back to USABDA, which could be collected and put on line, sent on CD to organizers of sanctioned comps, whatever.
Also, as competitor lists are starting to show up online ahead of time, it really does make sense for each of us to scan our events for people who jump out as not belonging there, and collect documentation if need be. Obviously this doesn't work so well with people you have never heard of before.
