When it comes to extremely rich people, "political prosecution" generally means that the behavior was absolutely criminal, but that it's usually something they let rich people get away with.
That said, I don't think your logic carries. Extremely wealthy people are often the targets of political prosecution because they're wealthy. Being wealthy makes you a target, it doesn't provide protection
Which wealthy people have been subject to political prosecution in the US that wasn't just a case where the person was totally guilty and deserved to be prosecuted, and it's "political" just because other rich people didn't get prosecuted for it?