Almost pulled it off.
My theory is this: He made the jump OK but lost the money on the way down. That’s why the money has never been found except for the decaying stack of bills found near a river a few years ago.
I also believe the best suspect was Richard McCoy who was caught and convicted of an identical hijacking only a few months after this one. This time the money was found in McCoys house.
McCoy later excaped from prison, went on a crime spree and was eventually killed in a shootout with police all the while claiming his innocence in the Cooper case.
According to the AP report, the FBI says that if this is his parachute, there is no way that money could have naturally reached the location where it was discovered.