If i understood it correctly, your VISA was cancelled by the company. Technically, you don't work for them and you don't need a NOC for that case, since it's more than a year already. but for the new law that was just passed recently, any individual who's visa was cancelled and wishes to come back to Qatar MUST get a NOC from the previous sponsor, otherwise you will be denied of any application for Visit Visa. I don't think your previous employer will exert the effort of giving you NOC, knowing that you won't be working for them the moment you arrive.
If i understood it correctly, your VISA was cancelled by the company. Technically, you don't work for them and you don't need a NOC for that case, since it's more than a year already. but for the new law that was just passed recently, any individual who's visa was cancelled and wishes to come back to Qatar MUST get a NOC from the previous sponsor, otherwise you will be denied of any application for Visit Visa. I don't think your previous employer will exert the effort of giving you NOC, knowing that you won't be working for them the moment you arrive.