Some minor threads left hanging...

i. The sheriff is going to be frustrated/ depressed that she is unable to bring Kurt Caldwell to justice. As far as she knows he fled Iron Lake. We know differently of course.

ii. The sherrif allows Harrison to flee unaware that he is an accessory to murder. That could come back to bite her in the ass at some future point because....

...

iii. Bautista is going to arrive to find Dexter Morgan dead, apparently killed by the sheriff. He's also going to learn that Dexter/Jim's son was in town and fled shortly after.

That is certainly going to raise a red flag with him and probably others in the town within a day or two. At the very least they would want to track him down to question him about how much he knew about his father's proclivities.

If they put out a BOLO for him, and he doesn't pop up in short order, that tells them that he's actively evading law enforcement which raises even more questions about his actions.

None of these points are a big deal. A competent scriptwriter could probably write their way out this, but they did stick with me after that final scene.