Just to point out – if they REALLY WANTED to do it, they could. Glee is not Universal and has used not only the songs but the characters, costumes and sets associated with Wicked in 2 episodes(and I will never watch them, lol). It’s also possible to work out a deal like was done with Quicksilver for the Avengers/X-men movies, I doubt Universal actually cares that much about a version of the character that’s probably different from the one they’ll end up using being put in a TV show, if anything it’ll help drum up recognition(but corps can be REALLY DUMB sometimes especially when it comes to copyright, so who knows). It will cost them but it might be worth it to bring attention back to the show since it’d be the first usage of Wicked characters outside of the book and musical.
This is why I’m hoping they put it on the long finger because they seemed to really want to get Oz right, and this might be one of the things they had in mind, especially setting up parallels to the Elphaba/Glinda story with Regina and Tink, which is useful for flashback purposes since they love parallels.
Most interpretations that have used Disney versions have been classic Disney movies – Oz the great and powerful didn’t do well critically or in the box office. It would make more sense to start over.
I don't cause commotions, I am one.