Martiage/divorce jurisdiction between Indian -Romanian citizens

Hi, there is a couple: he is an Indian citizen from Bangalore - NRI status, she is Romanian. 1. What is the difference regarding rights/restrictions of getting married in India ( Karnataja) and register the marriage that was made in Romania? 2. Does Romanian marriage is compatible with Indian laws for registering the marriage in India? 3 If an Indian- Romanian civil marriage is made in Romania, the divorce can take place by Romanian jurisdiction only? What jurisdiction is applied for a divorce in case of Indian -Romanian marriage registered in India? And in the case the civil marriage ( between Ro-In citizens) is made in India only the divorce can be done only by Indian laws or can be moved in Romania / by Romanian jurisdiction ? If the couple has a child before marriage born in Romania ( Romanian passport, and registered in India as PIO/ OCI- person of Indian origin/ overseas citizen of India ), if the couple divorces who is more likely to have the custody of the child in each of the marriage cases presented above? Thank you!