She got seats on the 5am flight on Swiss. $300 change fee. no additional charges.
I don't now how. One of the girls she is with used a travel agent, maybe they were able to do it for all 3 of them.
Thank you all for your tips.
They hung around the airport in despair for long enough that the United counter opened for their night flight. My daughter went to the counter and asked her to at least separate the flight home from the rest of the reservation so she wouldn't lose it. (I had told my daughter that if United replaced her 2nd flight (TLV-ZHR), she wouldn't lose the last leg (home), but in the midst of a crisis...) As the counter person looked into her reservation, my daughter asked for the 5 am Swiss flight. She was told that with the change fee, it can be done. (Although when the counter person realized it was X3, she almost backed out. )
Lounge passes for the rest of the night.
Thanks again everyone for your support.