Brother wrongly accused by ACB — how to defend him?

My brother, a lecturer at a private unaided college, was caught by the ACB in Thane in 2015, based on a student's complaint that he demanded ₹2000 for accepting a project after the submission deadline. Following a false inquiry, the private college terminated him. The trial is still ongoing, but there has been no progress. The law under which he has been charged applies only to public servants, yet the ACB has falsely implicated him. Due to his poor financial condition, he is unable to sustain his family. I need your expert guidance to file an application to get him relief from this case.