A player in the Baseball Junior World Series in 2001 was investigated because it was suspected his team falsified his age but it didn't come to light until after his team had won.
I believe the same thing happened w/ China's Olympic Gymnastic team. The ages of their team was questioned and additional proof requested after they won. And it seems to be similar to athletes being drug tested, investigated and losing their Olympic medals after they've won them due to performance enhancing drugs.
The pageant said they've requested info before from other contestants in the past and it was provided.
How is this case different that those above?
I understand the grandmother was born in another country, but a lot of US birth certificates include the city/state/country the parents of that child was born, so it's quite possible that info be on the mama's birth certificate. Mama dropped the issue, which I find odd.