Rape case after years.

Dear sir, My girlfriend(16.5 yr old during criminal offence) was in a relationship with a teacher(32 yr old during criminal offence), who was married and had a daughter, He mislead her by saying that he loved her and his wife didn't stay with him.The girl never loved her but because he had done many things for her she liked her, during that period he started coaching at his home and she joined it and he didn't take the fees from her, he gifted her much and fed her lunch for months and started being physical with her, she didn't understand this thing and eventually everything is consensual (he never told her the consequences and she thought, as an elder he will never do wrong to her) for 7-8 months, adding to this she also didn't denied because she feel intimated with that activity. After this period he dominated her saying you are only mine I have done many things for you, you can't talk to anybody and much more he hit her and now she started denying being physical but he forcefully did it. Though she still didn't understand that what he was doing was wrong. She(now 17Yr 4 month old) left the coaching after 9 months and started ignoring him but somehow she never have guts to get out of it because whenever she tried it he misbehaved with her and made her suffer in studies. She met her for only 2-3 times after she left the coaching, and eventually ended everything after she was 18 years and 2 months old. I met her when she is 18 months and 6 months old and she told me everything but she never understand that being in a physically relationship with married man is such a big deal and unacceptable to the society and she thought it's not her fault because he misled her by saying that his wife no longer lives with her and he loves her. But I scolded her told her that she has done something very wrong, no one will accept her even she was unfaithful to her parents. I told her that it was a rape and if society will ever come to know about this thing, it will cost much to her, parents, sister and brother. She is now in a deep regret and accepted that she lost everything. I somehow convinced her to do case. I somehow manage to gather the evidence, by building the trust of the teacher and he accepted me on video call that he was physical with her and he also accepted the same thing to the the girl on voice call, I have both the recording. he properly explained me and showed me the room also. he accepted that he was in a relationship with her and told me the duration of relationship also which is in the video call recording and also he accepted that his wife is mentally unstable, in that recording. He accepted everything to me in Jan 2023, and now the girl is 19yrs old, I am 22yrs old. I want to case after 1.5 years because of family circumstances, should it be possible? and can I be physical with her consent during this 1.5 years? and how I should proceed this case after 1.5 yrs?