Anybody has any experience with this kinda case.

I have two friends who won DV lottery and came here. They were married when they filed for DV but they said they were single in the DV application. They won the lottery and lots of people told them not to say that they were married. Both of them are here for little over three years. Now they want to bring their families (wife and two kids of each of their own). I know they misrepresented when they filed the DV and again when they won. Has anybody in this kinda predicament? If so...can somebody guide me how I can handle their case?