Divorce decree after 4 years and mutual seperation thorugh notarized.

I was married in may 2016 and she left me in july 2016. after meeting with our social leaders we decided to seperate in sept 2016 and we created a notarized faargati lekh(100 inr stamp paper). She married another person a year back and i am planning to apply for canada permanent residency for which i need a divorce decree. now the lawyer who created the stamp paper is telling me that divorce decree needs to be claim in first three years and now it is very hard to get it. i am in dilemma now as he is also telling me that i cannot remarry without getting the order from the court and she remarried which will create problems for her. the faargati lekh that he created clearly states that we are free to marry other people and if anybody needs a court order he/she can get it from court and other person has to help the first party. i am not sure as how should i get the divorce certificate needed to prove my marital status for my canada PR. Please help me.