A lot of people get whiny when they lose duels and refuse to verify. There are a number of ways to handle it.

First, you should submit the duel to JDC. Then, the best way is to be polite and take it up with them, talk about it, and nicely ask them to verify it. Talk to them first. If they are unreasonable or something along those lines, then talk to an admin (I'm probably the most available one this season). Use IRC or private messaging. I will hear your side of the story, and then ask to hear the other side of the story. The ultimate goal will be to talk both parties into being reasonable, so they either agree to verify the duel, or agree to delete it. If one side is unreasonable, then I will side with whoever is being reasonable and do what they say. If both sides are unreasonable and generally just won't get along, then I will simply ignore their complaints and any future complaints they may have, because I see no point in wasting my time with people like that.

In the future, if you have a problem, follow this advice and it should work out fine. Try not to post any angry callouts in this thread too, since it will just make other people fight back. The best way to deal with this is in private, not in public.