It is one of Berlusconi and Galliani, that's for sure. Maybe both. Berlusconi and Maldini supposly get along fine, there was a rumour Maldini even was one of the very few players that had his cellphone number. But Berlusconi is a politician, and a huge ego man. I can see him making it look like its Galliani who doesn't want Maldini there, while he washes his hands off of this, mostly cause he doesn't want a bigger figure than him there.
On the other hand Galliani never did once supported Maldini after his farewell fiasco by the Ultras. Maldini had trouble with him, big trouble. I wouldn't be surprised if Galliani doesn't want someone with the influence Maldini has near Milan. The fact that Galliani has a good rapport with the very same assholes that ruined Maldini's farewell can also be a factor.
Whatever it is though, it's disgusting. Big time, and a huge shame. If he's at disposal to work and help the institution as a whole, they can't be blocking him. Though I side with Gaizka on this. Maybe it's better he's out of there, he doesn't have to become a yes-man, which is something I doubt he'll tolerate anyway, though I sure hope he doesn't get involved with another club.