yeah, personally I don't see Henry letting his spare go without heirs of his own. he may be a second son, but Henry fought hard for this throne, and I see him being willing to do anything he can to keep a hold of it. Arthur may live to have sons of his own in this TL, but I can't imagine a legitimate second son going to the church. like I said, I can see the marriage waiting a few years, but not never happening at all. with COA being so religious, I can see her wanting one of her children to be a part of the church, but even then, probably only with a third son or even farther down the line. plus, even with (prince) Henry's marriage value diminished as only a second son, he's still not a bad catch at all; after all, at this point, he's not even of age, so he's still charming and handsome and all that, with all the promise to mature into a good duke.