Here's the thing. South Park's disclaimer is a joke. Not only a joke because of its hyperbolic wording and the fact that it's not true---of course the show depicts real people all the time, including celebrities has been a staple of the show since the beginning. But also a meta joke about how pointless a disclaimer is.

We read the disclaimer, it looks official, we see that it is a lie, we ignore it and we watch anyway, with our experience unchanged. Nobody ever thought "this Kanye 'Gayfish' West character is incredibly similar to the rapper Kanye West...what a coincidence!"

I guess my point is the South Park disclaimer pretty much puts to bed the idea that a disclaimer does anything at all. If Hannity gets a disclaimer, nothing will change. Seeing the disclaimer will just get these people hyped for incoming Hannity, the same way the South Park disclaimer works. It will make his show more effective. That moment of recognition and suspense before the theme song starts... it's great when you see the South Park disclaimer, right? And then you proceed to watch the show completely disregarding the content of the disclaimer.