A way I’ve recently thought the show should have gone, if they were dead set on not having Jon be the one to kill the NK

Have it be Beric Dondarrion

Yes I know, he’s dead in the books, but they didn’t go that way in the show. The more I think about it the more it would have been an amazing hidden in plain sight moment all along

He religiously follows the Lord of Light, he’s been resurrected more times than anyone ever has been, the Brotherhood without banners literally “unites the realm” in the fact that they come from all walks of life fighting under one (lack of) banner, and he literally has himself a flaming sword.

I haven’t looked into Targaryen marriages outside of monarchs; maybe there could have been some 3rd daughter of a 2nd son that wound up marrying a Dondarion lord; so from Aegon’s line did come the Prince that was promised