Married while Divorce pending but later after second marrige .

My Friend applied for 13b with her wife. on Sept 2019 six months has been granted for completion after second motion on Jan 2020 next due date was 4 april but due to lockdown it all postponed. later court was vacant. my friend married with an girl on jan 2021 informing about his divorce situation to girls family. they agreed that after divorce they will do court married but in Jan 2021 they got married using hindu ceromonies. later divorce decree was granted on Aug 2021. but now current wife threatning/blackmailing that as marrige is void and she will file case for this as he married during pendancy of divorce. i understand that it is unlawful to marry while pendancy of divorce but all facts were stated and divorce has also been granted from first wife. but still what he can do to overcome this situation keeping in mind both options eiter to live togather or get seperated.