I feel Air India did atleast the basic thing with your daughter by providing a hotel and food vouchers. The flight delays were due to the reasons out of their control. However, I would say, they should make themselves more prepared to such unexpected calamities and should have some contracts with other airlines. I guess if the flight was from LHR to some indian destination, they would have arranged some seats with code share flights but to US, it is not possible. And this is where they need to work on.