I refuse to believe that evil twink Grayson managed to pull the hottest character in this ...

Seriously, judge Grayson after you read his novel. He's not that bad as most write here. Doesn't mean that he is not problematic etc., but he is not evil.
Yes, he got Dane. And that pair was planned from the start, since Grayson's story was the first that author came up with when she started with omegaverse.