Not a bad move, to spread some of that wealth around in Bitcoin, he'll probably a lot of more money (in terms of fiat value) since the price could shoot up in the long-term, and those 5m could turn into a lot more.
"the expert told Cosby of Bitcoins privacy and legitimacy, as it couldnt be taken in a divorce..." the guy probably made up his mind after listening to those words LOL I wonder why they didn't buy more, I probably would have if I had a $500 million fortune.