Changing Government Job Without NOC or prior information to previous employer

Hi, My selection in Lecturer Grade in Uttar Pradesh Suffered due to one person who joined inplace of me due to slight margin of marks. I was enquiring about her past jobs and found as below: 1. Firstly he was employed in Basic Education Department and During the probation period he gave a application of unpaid leaves of 2 years. On 21/05/2015. As per RTI his application was not accepted and he is marked as continuously absent from then in his primary school. 2. He Joined Higher Secondary School as Lecturer the next day of giving Unpaid Leave Application to last employer. And worked for around 1 year there. He then gave a resignation stating family problem on [deleted] to the employer. This was also not approved. As per RTI he is also continuously absent from that college till now. 3. He Joined in a new school as lecturer on [deleted] hiding the fact of previous post or resignation. Neither he obtained NOC from previous employer. He basically resigned from last post as he was working in a different district which was far from his hometown and this time he got job in his hometown in the same department and same position as previous employment by hiding the facts. Can I Challenge his latest appointment and what are the grounds to challenge his job?? Please guide me.