Any one can ask for forgiveness. They have to ask Jesus into their heart and confess Him as Lord and Savior to enter His Kingdom. You said sin has no bearing on anything in the end, but Romans 6:23 tells us different. "For the wages of sin is death; but the Gift of God is eternal life through Jesus Christ our Lord". If OJ didn't accept Jesus as Lord and Savior, he is none of His.
Where is OJ today? God only knows...
Hope you are well brother, stay safe.