There are many such languages with script which are not in eight schedule like Tulu and Kodava.
Not only urdu is scheduled language but even Arabic and Persian are. One can take Civil services exam in these language.
There are two things one is sizable votebank and second is political will of people.
No. With this I mean, in Deccan, I have seen advertisements written in Urdu while in UP I have seen only in devnagri.