Foreign Nationals with OCI living in India seeking Divorce

Hello, I am a New Zealand Citizen (Originally Indian) by immigration and hold a New Zealand Passport. My wife is a Russian Citizen. Our marriage was arranged in India, and I later invited her on a "Culturally Arranged Marriage Visa" as she was a practicing Hindu. Our marriage happened in New Zealand according to Hindu Vedic Samskaras. We have two children , an 8 year old girl and a 6 year old boy, both NZ Nationals and NZ Passport holders. We moved to India around July 2013 and have since then been living in India.(Our kids have OCI status too). In June 2016, my wife was caught cheating with another man. I have some communication and photos as proof of evidence. Later, with the help of our community, 4 counsellors sat with us and she agreed to her mistake in front of them and we decided to forgive and continue our marital life for the sake of the kids. She has gotten into another relationship with another man now and wants to move on. She has moved out to another house close to this man. The kids are under my shelter. She has agreed to a mutually consented divorce, not claim any alimony or share of assets, and has agreed for the kids to be under my guardianship, and the kids shall live with me. Do we need to apply for a divorce in NZ or in India? We have pretty much lived separate lives since her June 2016 affair. Does this constitute separation? Considering our Domicile is now India, would we be able to apply at the District court in India? Our marriage was a Hindu Vedic ceremony - Would we be considered under the Hindu Marriage Act? In New Zealand, we have to show two years separation. But I ave not filed for separation papers there. Also, possibly, one of us must be present in NZ to apply there. She is of the opinion that she can apply for a divorce in Russia, being a Russian Citizen. I am not too keen about this as all decrees and paperwork will be in Russian with absolutely no way for me to know what transpired. If she goes ahead with a Russian application, can I disagree and get it quashed from an India Court of Law? Any information will be helpful, as it seems to be a complicated situation. Kind regards.