Not gonna lie, I'd love to see the duke being Lex when the prince decides to attack Erin. The prince being absolutely terrified of Lex's lovey-dovey optimism combined with cold blooded touch-my-wife-you-end-your-life measures.
But here's the thing tho. Lex might be her ideal guy but the compliments he spouts is the same ones Rowan would give without all the icing sugar. See how he tried to deny it here? There's no way all that the love lex gave her was entirely meaningless. Thatd b e a seriously awful conclusion if he was an entirely different person altogether