Responses
I wouldn't be surprised if she came acrossed someone in the Crown Prince's place that knew her from when she was a princess.
I can already see it.
"Princess!? Is that you?" Σ(っ°Д °;)っ
That or she tells him herself after finding out that he doesn't want to kill her.
We won't know until the idenfication unveiling chapter updates in the future.
╮( ̄▽ ̄)╭

Umm.... my question is... how are they gonna find her anyways?...like isn't the only portrait of her destroyed.. are they looking for blondes since her step siblings were blonde/blond..... or... like how tho?.....