I agree that Jason was involved in some way. I felt that right after the night of the Bronco chase.
If you recall, they chased OJ back to his Brentwood home. From the helicopter camera view you could see OJ and Jason screaming at each other on the lawn as OJ drove in.
This was not the type of interaction one would expect between father and son at that moment. But it did look a lot like what two crooks would being saying to each other if one botched a job and both were about to be arrested.
I think OJ did it but Jason assisted with it and helped cover it up. Likely OJ and Jason were both angry about Nicole sleeping with Ron Goldman while living off OJ’s money.
Just my two cents.
I believe the same also but with a twist. I believe OJ knew that Jason killed them. This kid is big and tall. I believe that night Jason was with OJ at the Rockingham home went and killed Nicole; Jason returns and OJ sees blood on Jason and drips on the floor; then he himself drives to Bundy where Nicole lives only to be shocked in horror how brutal the killing were. I believe his pointing his gun in his head was a father in distraught whether to hand his son over to the police and get the death penalty OR be the fall guy so his son can have a future. OJ always knowledge that he was not a good father to his kids. I believe this is his way of returning some sort of acceptance or Love to his son.