I made a comment awhile back about Dante and Sam looking like siblings. But even though it was weird, the writing made them friends and supportive, which was much better than this mess now. You need physical chemistry to pull off the verbal thrust and parry antagonism leading to sex thing. They don't have it.
If they absolutely have to pair them up, they should have stuck with the friends route. A low key friends with benefits leading to something deeper over time might not be exciting but at least there would be a bit of angst when Lulu comes out of her coma.