Does Chapter 30 say anything about whether Sai Baba knows the inner thoughts or desires of his followers?

Yes, Chapter 30 explicitly addresses this. The text affirms Sai Baba's omniscience regarding His devotees' inner states, stating, "Sai Nath knows completely the heart's desires of His own devotees." It doesn't stop there, but also emphasizes His capacity to act on this knowledge for their benefit. The verse continues, "He alone is capable of fulfilling them. Therefore, His devotees become fulfilled." This highlights a core teaching that devotees' deepest longings are not only known but also brought to fruition by Sai's grace.