Besides the local villagers, were there other holy men who recognized Sai Baba's greatness early on?

Yes, other spiritual figures recognized Maharaj's worth before he became widely famous. Chapter 0 mentions two such individuals. One was Gangagir Baba, who, after having affectionate conversations with Maharaj, referred to him as a "gem" of great worth. Another was Anandnath Maharaj of Akkalkot, a disciple of the famous Swami of Akkalkot. When some Shirdi residents visited him, he insisted on accompanying them back to Shirdi. Upon arriving, Anandnath Maharaj declared about Sai Baba, "This is a diamond. You don't know its true value. Even if he is on a dunghill, he is a direct diamond." This shows that other enlightened souls perceived his greatness early on.