They could have/SHOULD HAVE used this as Trump's reason for demanding a copy of Obama's birth certificate.
It then becomes a tar baby. It is lose-lose for Trump to start discussing it again. The MSM will report selectively on what he says and use it against him. As Trump says, he finished it. I fully anticipate it will come up at the debates. I hope Trump deflects it and says that there are more important things to talk about and Obama is not on the ballot.