Here are the several options she has:
1. DNA test. Match it with that of her parents..make sure Mallika does not get it changed by bribing the doc..
2. Call Nandini, divya dutta and all other people who were involved in her makeover. They are witnesses.
3. Call Nandu to witness box and even Purab
4. Call any of the gang members and ask them to ask her anything about Jassi..
I don't think she needs a lawyer, she just needs some brain..