Is Nikah Nama enough for filing i-130 for spouse visa


I have a question. My sister had Nikah and she has a nikah certificate. Is Nikah certificate enough, to file for spouse visa?? I read it on US embassy India that a person marry in Muslim, Christian, Parsi… They are not required the marriage certificate.

But my concern is, will they ask for it at NVC stage?? @anil_am22

This below website, I read about it. What you think on that?