He had money and lawyers - resources no normal person has, and he had a narcissistic personality. Think what you like: Multiple broken cervical vertebrae and broken hyoid bone, at his own hands, just with a sheet, with no drop?
Again if or not he had ˜help” the guy wanted to be dead rather than face life in a prison or his death by other hands than those he preferenced.....his own and or with help if necessary....and at a time of his choosing.