Birthday wish for 10 year old budding cellist

My daughter is turning 10 in May and I asked her if there was anything she wanted to do or anyone she wanted to see in concert. She said, "Yes! Yo-Yo Ma!" This is her first year playing the cello, her 12 year old sister plays the violin, and my 13-year old neice that will be in Chicago to celebrate her birthday with us is an incredibly talented strings player that plays violin, cello, and anything else with strings. I think it is so special that Delaney asked to see Yo-Yo Ma, and not Adele, Taylor Swift, Selena Gomez, or any mainstream kid-rock band. I didn't even know she knew who he is at such a young age. I went on the Chicago Symphony Orchestra webpage and called the number. The gentleman said that the tickets for the weekend we are there...May 4, 5, and 6th are sold out. I am heart broken. I wanted so badly to make this dream of hers come true. Does anyone know how to get on a cancellation list or anything to purchase 6 tickets for either the Friday or Saturday (4th or 5th) show? Please help...