Since I'm not a lawyer, why would there be settlement if Doughty was convicted of any thing and presumably did nothing wrong? If anything, she owes him money for wrongly accusing him.
I am not a lawyer either, but I am a retired LEO who knows more about the law than I ever wanted to, so I'll give you an idea how this works.
First of all, she owes him nothing. Nothing at all. She made the accusation, and the prosecutor decided not to file. That's it. If he wants to sue her for making a false accusation, good luck to him in trying to make THAT stick. (Not gonna happen.)
Second of all, you are partially right in that since there was no conviction, it makes Super Glo's efforts at collecting a significant portion of that $56 million wad much more difficult. However, that is not the way the real world works...in other words, Doughty's attorney will probably convince him to part with a minuscule amount (minuscule to him, anyway) just to make the ***** go away, and ensure some of the more tawdry info between the two doesn't make it into Entertainment Weekly or The National Inquirer or some other rag.
Lastly, and as a matter of legal smarts, Doughty needs to find another squeeze. Hopefully he is smart enough never, ever, to touch base with this woman again. Hopefully.