Bigamy or sec 494

Respected Professionals,

   I have So many doubt in my mind so I am telling you my complete Marriage situation and need your valuable suggestions.

My name is sourabh and got married with Pinki in Jan 2016, After 1 year of marriage I came to know that she was already married with someone else (Muslim Boy). Still I understood her and we start living accordingly. there were some querrels in the family as usual with my mother some time with me also. but as she get pregnant she totally changed and she just saying that she want to live saperate from my family, she want that I should leave my parents. I tried to handle the situation but she is not ready for any other option, Pinki has totally set her mind to live saperate from my family for which I am not ready. I cant leave my parents How can any one leave his/her parents without any reason. 

  Now she is threatening us that she will commit suicide and file a false case, She will file a false dowry case against us. Her Mother is also encouraging her rather than to solve the matter. Her mother is on the daughter side and not trying to end all this. Her mother is saying that We should give her One House and then Pinki will live saperate from my family without taking divorce. 

Mother In law teaches every step and every thing to Pinki that what should she do. I also tried to talk with pinki's father but he also not shows any interest in this. He is also not saying anything to his daughter. I am not getting any support from my in laws. 

Now at last I decided to go for the annulled marriage as she is already married with the other person. Because this is the only way I can get rid of this problem. 

I tried to collect the evidence of her previous marriage. 

I Got the FIR copy of Missing of Pinki from the Police Station. Under this Complain Pinki's Father had lodged the complain against the Boy U/s 363 and 366 i.e. for Kidnapping and Marrying forcefully as you know.  In the same copy There is a note which is mentioned by the IO as the Pinki is Mojor, and she married with Saif with her own concent and there was no kidnapping of pinki.

Got the Court Judgement order that Mohd Saif (boy with whom she got married), is not guilty in case 363 and 366. there are no solid evidence that proves the above sections on the Mohd Saif.  

Pinki's Statement in the Above judgement: I am major and I can understand my good and bad. I am totally responsible for all this thing. I gone with Mohd saif with my own concent and Converted my religion from Hindu to Muslim and got married with Mohd Saif with my own concent, I was not kidnapped. 

Saif Statment : We got married with own mutual concent. I didnt kidnap Pinki. She was ready to get marry with me. 

On the basis of these statment and Police verification the Case was dispossed with decision that Saif is not guilty for the Kidnapping. 

Pinki has also filed a writ petition in Honble Allahabad Court for the Protection of her and her husband. I have also got the copy of that order. 

Now my question is that :

1. Can I file a case on the basis of these evidences. As i tried to get the marriage evidence, but the marriage was soleminised as per Muslim Customs. 

2. Can she file a Dowry case or domestic voilence case on me and my family if I file the case for annulled. 

3. What if she got the Divoce as per Muslim Cutome Like Talak word. Is it valid in my case. 

4. as she has not converted from Muslim to Hindu. Is my Marriage legal with her.

5. Who will get the custody of Child. (she is Pregnant with 3 month)

6. what should I do first to file the case against her for getting annulled this marriage. 

7 Should I need any other evidences to prove her marraige.