Wife cheating with multiple affairs

I found out that wife is cheating with multiple affairs at least 3 people I know as of. Caught her talking to those guys daily over phone and WhatsApp. Also one of the guy is sending her money monthly to her account. I found her scolding that guy many times and demanding more money. I found another her affairs after she got pregnant. For the sake of foetus health I’m keeping quiet now and she have no clue that now I’m aware of her affairs. I started recording her conversations once I got suspicious. Saddest and disgusting fact is that her mother is aware of all these and she is encouraging her to get money from them. She even guards her during her talks with those guys and let her know when I go home and stops the conversation. What is the way to go now. Should I contest for divorce or ask her for mutual. I’m afraid if I ask her for mutual, she will definitely put case against me n my family with dowry and many others to torture us. Can the recordings be sufficient to prove her adultery and get divorce. Only reason I’m waiting patiently to file for divorce is the baby. I need custody of baby as her n her mother character is not good and that will spoil baby’s future. Her delivery is due in couple of months. Please help