We had a cross beak sultan. He was an amazing chicken and by far the friendliest of all, but he couldn't eat on his own after several months and was slowly starving to death. We could have crop fed him and discussed doing that since we both loved him so much, but we thought that overly traumatic to do daily for the rest of his life. So we decided to try a debeaking, it was either that or to cull. And neither of us could do that to him. The debeaking was gawd awful terrible to do, and most likely hurt us nearly as much, but he did really well after that and the cauterizing. He could finally eat somewhat like a normal chicken. But I think in the end his overall weakness got him. The debeaking gave him several more months of a good life and he was able to join the flock and be a chicken, which made us really happy. He died about 6 months old, he never was a hearty boy, but we think he had a great life, even if short. He got lots of mealworm treats and he would sit in my lap, willingly coming to me and hopping up. I'd preen him and give him lots of love. When he had enough he'd jump down and join the flock.
My hen Flossy is his egg mate, so I have special affection for her too. I keep marking her eggs and hoping one day she throws a chick which has his overall look and height(he would have been a large boy), but be a healthy rooster.
Here's CB before his beak got too bad, since it hooked more and more as he got older, and another with a more mature CB after his beak job. It wasn't pretty.
I've had two cross beaks born out of my eggs from my old rooster. Both were also missing a eye and I had my husband cull them. I couldn't grow that attached again like I did to CB, would have broke my heart to loose them. Thankfully with the new rooster I have not seen that defect! My avatar is baby CB, you can see he did not have much of a cross beak at hatch. I never imagined it would get as bad as it did.
I don't mean to discourage you from keeping your crossbeak. Some people have a lot of luck with feeding them mash or wet foods, and most will not get a hook like my CB did. If not for that hook in his beak he may have been just fine. Just be prepared for the future, you may have to crop feed by tube or make special foods for your crossbeak. Mine broke my heart, but only after filling it full of love and not a day goes by that I do not miss him. He taught me just how awesome chickens, and sultans in particular can be.