Crossposting the same question would be in violation of FT TOS.

EU laws don't really apply as this was a 'direct' flight India-USA. The delay option were provided to the OP, but as he had no visa and the immigration authorities refused to help AI would be in the clear.

While the ordeal the OP went thru is certainly not something nice, AI cannot be held for any legal responsibility. I would certainly protest loudly to AI and the TA who arranged the tickets and see what happens. Don't get your hopes up high.