He probably didn’t make a run in the beginning because he had convinced even himself that he hadn’t done anything wrong, that he’d just been aggressive and sloppy. Then he probably thought that he might be accused of something, but that his money and connections would help him stay out of jail. By the time he was arrested in the Bahamas, it was probably too late. He was too high profile to just slip away.

If he’d been a bit more paranoid, he probably could be on the run today.

He had access to billions. Even if getting it all liquid would have resulted in a 90% loss, that’s still hundreds of millions. With that kind of money, you can find a country where you can get a new passport under a new name, and probably get away with faking your own death.

The problem is that to do any of that, you’d have to work with other people, and there would have to be some trust involved. If he wanted to keep the money in a bank, there would have to be some mutual trust with a bank / banker. If he tried to walk around with millions in jewelry, he’d have to avoid getting mugged. If he hired private security, he’d have to avoid getting mugged by his private security. If he tried to use his money to get a passport in say Myanmar, he’d have to have some trust that they wouldn’t just imprison him and beat him until he gave him the rest of his money. If he had tried to work with a lawyer who was only slightly bent, he’d have to trust that the lawyer wouldn’t turn him in. If he had tried to work with a very bent lawyer, he’d have to trust that the lawyer wouldn’t have him tortured until he gave up his money.

While he was definitely a criminal, he was a white-collar criminal from a very white-collar family. He probably had zero connections to underworld figures. So, risking his life going on the run might have seemed like less of a risk than risking that his money and his connections could help him avoid prison time if he didn’t run.