.... I'm assuming she plans to go to the American falls - I have been to them from the Canadian side and it was very easy to book a trip from the hotel, but you are talking about a very long way from NY to Niagara!!
We saw the people on the American side in yellow ponchos walking down the side of the American falls - I don't think they get much of a view of the Horseshoe falls (the part of the falls you see in all the tourist shots), but possibly a helicopter flight is offered over the falls and they may want to consider this too so they see it all.
Helicopter flights were offered as an extra when we went on our tour on the Canadian side, and my sons and DH did this.