Wife concealed her first marriage

My wife was married and got divorced from her first husband. Initially she filed a case of 498A and 377 against her first husband, however after six months they got divorced on mutual concern. She got married again with me and had hidden about her first marriage. She had also signed the affidavit in marriage registrar office stating that this as her first marriage. The cheating has been discovered after 6 years of marriage now. On asking she attempted to commit sucide twice. Now a case for voidable marriage has been filed in family court and a police complain in this regard has also been lodged against her and her parents for fraud. Now she is ready to seek divorce on mutual concern. So the questions are :- 1 weather going for divorce by mutual concern will weaken the case? 2. What if she denies for divorce after six months of separation period 3. Will this ground of voidable marriage be vaild again ? 4. Weather I should go for divorce by mutual concern or contest for voidable marriage ?