Sorry, I was in a rush.
There is Person A, who is claiming to press charges for libel, but does not know exactly who is behind the account name. She knows of 2 people and believes it is 1 of them, who might be the 'offender'. She does not have any proof to show either possible suspects are the 'offender', other than her own assumptions.
Can she continue with pressing charges, if she does not know exactly who is behind the account name?