Now there is a lot we aren't told about here. How could a mistake like this possibly happen? Did the conductor do it on purpose? Conductors can sometimes be amazingly cavalier with their soloists. Preparing to play a concerto is one of the most demanding tasks there is for a performer and, unless they had just been playing this piece a couple of days before, so that Chailly knew for sure she was ready to play it, this is the kind of thing that could get a conductor blacklisted amongst soloists! Every solo performer works very hard to make sure they are never caught in public playing without adequate preparation so it would be very tempting for the pianist to just get up and walk offstage, muttering to the conductor, "let me know when you find the parts to the right concerto". It might make you look bad, at least until the facts come out, but they sure aren't going to be able to go on without you!
Wild things happen in concerto performances. Arthur Rubinstein tells the story in his autobiography about the first time he played with the Berlin Philharmonic. As I recall he was quite young, perhaps twelve years old. In any case, he was playing a huge and demanding piano concerto by Brahms. It went quite well, but when he went back onstage to play an encore, as soon as he sat down, the piece he intended to play just evaporated from his mind--a complete memory lapse! So he improvised something. Well, that was Rubinstein. Pepe Romero had a bad memory lapse in a concerto. He was premiering a concerto written for him by an American composer and it went quite well. In the second half (only Pepe would be playing two different concertos in the same concert) they played the A major Guitar Concerto by Giuliani, which Pepe has played a thousand times. Everything was fine until the last movement, a rondo. Pepe had a memory lapse near the beginning and just couldn't pick it up. So the conductor stopped the orchestra and began again. Same thing. This happened three or four times and finally the conductor launched the orchestra at a blistering tempo under the theory that if Pepe was too busy to think about it, he probably wouldn't have the lapse. And so it was. But there is another story about Jascha Heifetz that he had a memory lapse in a concerto so devastating that he walked offstage and never returned.
That's all the concerto incidents I can recall at the moment, so let's end with some Heifetz. Here he is playing the first movement of the Tchaikovsky Violin Concerto: