Returning a wallet is a great thing, but maybe (if ID was available) you should post the name of the person. Only a handful of the disc golf community in KC uses this message board with any regularity. Rosedale has a large number of casual players that would never come to this section of the website. It is possible that one of the people that uses the board frequently may know the person.
If you are worried about giving the wallet to the wrong person you could always make them provide some other form of ID.
It is a great thing to return something that another has lost and you deserve all of the good karma that comes to you for doing it. Naming a name would only increase the possiblity that it returns to the rightful owner.