Salam folks,
I just want to throw out something since I also learnt this thing . Yesterday I submitted my file , my wife sent me things from Pakistan which was her part. I used to think from start that marriage certificate / registration they all mean NIKAH NAMA of URDU/ENGLISH, but in reality their is a thing like this. My wife sent me a greenish/yellowish paper both were almost identical and were called Marriage Registration and Marriage Registration Certification and had info exact as Eng Nikah Nama.
Just throwing out if this can help someone. Also, you can only get this once only when Prin App changes her status in Pakistan , so start with smart copy then passport so you have everything updated in NADRA.