Theory about Quinn in season 2
I think Quinn will cover for Dexter because throughout the series, he and Quinn have covered for each other several times. Quinn also doesn’t have the same mindset as Batista, Doakes, and the others. He would understand that you don’t necessarily want to put people like that behind bars, especially since he wanted to kill Oliver Saxon himself in the final season and he supported Dexter in doing so.
He would also understand that Dexter never wanted Batista, Doakes, or Debra to die, because Quinn has had similar experiences himself. And if Quinn simply turned Dexter in, it would basically be the same as in the first season.
I also think it’s very unlikely that Quinn will actually manage to put Dexter behind bars, especially since the plan is supposedly for the story to last three seasons.