Well, I do not 100% agree with Tito-Satya that Nicky might have done this for publicity stunt, but yes, it can be one of the reasons..
Also she does not have any solid proof to assert her accusation... so she might be in trouble for sure if there is a lawsuit...
I heard Susil Nepal's phone interviw in sidhaa sabaal, and appears he is innocent. Now, one person is accusing and another person is denying, so there comes the play of proofs and evidences and looks like Nicky does not have any to support her claim...

Good Luck Nicky! Dashain ani Tihaar raamro hos, tara laag6a timro dashain ani tihaar raamro hudaina yadi Susil le case garyo bhane..