Which just means that the driver hasn't actually been changed since then, which is probably true.
JRiver used to update the WDM Driver with each update, and give it a new version. But every time they did that, Windows removed the WDM as the Default Audio Device, so people had to go back and set it as the Default Audio Device again after every update. Updates, which you would be aware, are quite frequent. So that was annoying. The installation/update program apparently can't remove the old driver, install the new one, and then set it as the Default Audio Device, because it is a different driver. I believe it is a Windows security issue, to prevent drivers from making themselves default. But I'm no expert on that.
The point is, does the WDM Driver work? Okay, then don't worry about it. Just use it. Rename it to "JRiver Media Center 26" if it bothers you aesthetically.