Well maybe your cousin isn’t born again because Ephesians 2:8-9 clearly speak AGAINST belief in Christ as a work that we can earn.
I've had that thought as well and we've gone through The Gospel step by step (faith that the death, burial and resurrection of Jesus Christ is all that you need to be saved) and he says he believes, "but" he must do good works and using govt to that end is good. I've told him his works are nothing but filthy rags but he doesn't want to hear it.
He claims he's a Born Again Christian and I think Jesus will be the judge of that.