You have rightly mentioned that being employee of the company you have limitations to complain against the employer company, hence the "Sansad Rajbhasha Smiti" should act and inform you on the outcome.
Have you received any reply?
You had posted the letter posted by N.Toppo earlier also. Have you received any more updates, results, after the letter of N.Toppo?
NIACL is compounding the issues and its problems. Their mindset is let the court decide and let the legal cell approach higher court and so on. And /or crop up other issues if reinstated. However you seem to have enough records and evidences to thwart the mollified intents and practices of the offender and corrupt employees of your company.
In labor court if the basic law in the case is not questionable it shall be difficult for the company. Your case seems to be in accordance with your basic lawful rights.