American Idol Audition?

Hi have a younger sister who is going to audition for American Idol
the only problem is she is about to get her name changed so she is
really worried that her name and her new birth certificate won't be
done by the time her American Idol audition comes what can she do if
she's in the process of changing her name? I am really confused so I
decided to ask here please its her dream to sing so I really want her
to be able to have this opportunity so what can we do if she doesn't
want to use her real name until her name is changed please I really
need suggestions cause I really don't know what to do if she doesn't
want to use her current name until its changed thank you for your time
and answers :)