He won't go to jail. He is a member of the upper crust of our aristocracy, and we live under some kind of feudal/monarchic system nowadays.
He currently has no money, and he ripped off a lot of people with money. He'll go to jail.
https://www.marketwatch.com/story/there-is-no-innocent-expla...
If they can prove it was fraud he'll be going to jail. Depends how smart they were and how well they covered their tracks.
1) They still have money (he doesn't seem to have so much anymore)
2) They already traded money for power so people feel they owe him favors (no indication of this)
3) He didn't screw over other rich people (seems he did screw over other rich people)
The third one in particular is important. Messing with other rich people's money is far and away the easiest way to get yourself thrown in jail despite any wealth you might have.