Major accident recovery done employer avoiding re-joining what to do

This is related to my brother who was working in MNC in Noida, had major head accident in Sept 2015 incurring partial loss of memory & weak mental ability. Under treatment for around One year. Company was informed about the incident. After One year with some re-gain in memory,we tried for re-joining but company avoiding employment & when tried to put pressure for re-joining,asking for amount back transferred as salary during that period. Till now we not received any termination letter or resigned from the company. Please advise on the above matter. We would prefer to file case from Lucknow Labour Court. How should we proceed?