Sorry to hear this chick ended up with a cross beak. There are different theories on why it happens from genetics to temperature fluctuations during incubation (usually too high, I think). Depending on how severe it turns out, if you're willing to file down its beak every week, it should be able to live a pretty normal life. Won't be able to forage as well as the others, but we're going to be celebrating our cross-beak roo's 1st year birthday in two weeks. He's a perfect EE roo (who will never be bred in case it was genetic) and he's second in command of the 3 rooster flock he's in.
There are some people who've used massage or some cream to help loosen the muscles along the neck which have helped, but mostly its a skull deformity. Not sure how much we can control how it will grow.
As long as you keep beak a workable length and they can feed themselves, it should be fine.
Good luck!