If avoiding prison was all he wanted he could just release his medical records. The one who definitely don't say he had a series of strokes.
He's a powerful narcissist, with probable dementia, surrounded by yes-men very heavily invested in this election. I'm not even sure he even has the capacity to fear legal repercussions for his actions.
Trump planned for and started this run years ago when his dementia wasn't nearly as advanced.
Besides, plenty of people with serious mental conditions go to prison. There is only one reason he won't be one of them. He's wealthy and only the first part of "Liberty and Justice" applies to him.