Existe outra maneira válida - preencha um segundo DS-160.
Existem outros usuários on-line com o mesmo problema e um chamado EUA Embaixada para verificar :
I called the London Embassy to confirm that filling out another DS-160 wouldn't produce any problems, and they said that there is no way to retrieve an application ID and that filling out another DS-160 is the only solution. They also said that it would be the same if I had made a mistake on my application and needed to fill it out again and I had forgot my ID.