Victim of marriage fraud, what are my options?

My soon ex husband of 1 yr/7 months has strong evidence against him that he committed marriage fraud. Our case was very complicated as we had to get/win the extreme hardship waiver as he had numerous visa violations. We formally married in Nov. 2014, filed in Feb 2015, he received his 10 year green card Fall of 2015 (our lawyers had us common law). 1. Although he did not disclose it, he was engaged to be married to another US citizen the same month he met me and wanted to live in the us/get a green card from her. She broke it off & her ring is my ring. In his I-601 statement he swore he had never had an intention of moving to the us or settling down prior to me. 2. He has 2 children in the UK (his ex wife is deceased) that he did not disclose. 3. He had numerous documented affairs prior to/during our marriage & is now living with one of them. 4. Statements where he told persons his only reason for marrying me was citizenship 5. He told his former UK employers his plans.