Dear Anand,
To answer your question, "Do I have option to go the labour commissioner / labour court?". - Yes you have that option open.
But do you have proof that they did not allow you in the office, as you already said, that the online attendance is still live, so you are anyways marking the attendance, but as there will be no corresponding work, they can still terminate you.
Also if the offer letter clearly mentions that you can be terminated if you fail to meet the assigned targets, which i presume have not been met and as you have already signed that letter, what can you challenge in the Labour Court.
In regards to the F&F, they still have time to do so as it has to be done within 30 days.
So You can approach any court, but what can you prove in that court, plus the decision will be pending till the case is heard, which will take around 3 - 4 years to clear, so you can wait till that time and also try explaining any prospective employer, that you will require leaves to attend the labour court, as there is a case you have filed... You selection itself will be a question mark.
My suggestion:- Forget the Ego... Speak with the management, and resolve it amicably.
Regards,
Ashutosh Thakre