When I read the 'beauty' "have black hair and red eyes"… I immediately think that maybe MC had typos and she accidentally mix it and instead she writes "red hair and black eyes" … cause that usually happens to me and my classmates
at the end of ch29, he finally is able to see colors it seems. This was a painful chapter where he was almost at the door of making the prophecy true. Like the prophecy said he was blinded. In his dream he was shown the true colors of people where those people talk about killing him but they wanted to keep his beautiful face so they ,even the king who is Rayn's father, talked about keeping his head unscratched. Those words drove Rayn to the brink of choosing death but at the last moment he was reminded of Prim. He thought who she would look if she was to never wake up from sleep. Then thinking about her took him to the memory of cherry petals and her in the rose field. He first saw the color pink in the petals which he tried to catch but failed and then he followed the petal to reach Prim. this meant )i guess) his choice. He chose Prim and to live for her. Then he woke up and saw his ceiling which had colors, the colors he had never seen in his life.
the reason he was blinded could be in my opinion his despair. when his mind came to the conclusion that Prim was not his destiny as he could not see colors even after meeting prim and prim clearly said his destiny would make him see colors, he was broken. His despair took over him and his reason for sanity broke. which was why he was shown those hurtful words of those nobels and his father who only wanted him for their greed where as Prim was the only one who wanted his happiness. So he, with his last bit of sanity, chose Prim. and yes, she was his destiny.