It is better you let her withdraw DV. Please apply for certified copy of the Case withdrawl prusis. The order which has been passed by JMFC court is a valid order till the time any civil court like family court passes the final order.
Session court will not set aside the order passed by learned JMFC.
Custody matters are civil matters and have to decided by the Family court or civil Court. IN DV you can get a temporary relief.
You being the father of the child have right to be with the child. It will be better if you file a case for custody at the appropriate family court under GWA.
Incase you have filed a Divorce case, the custody of the child can be decided u/s 26 of HMA.