Idk but in season 2 when dexter found out from Matthews that Harry committed suicide and Dexter always thought it was bc Harry saw what dexter had become I just didn't buy it since Harry groomed him to be that way in the first place as a way to channel his "Dark Passenger". And it'd be a good twist since we have the unreliable narrator in Dexter; since Dexter's projection of Harry is based upon his memories of Harry which happened to be shaped in part by how Dexter remembers him and what others have told dexter about him.
And with the new British psych lady having a connection with Matthews and Harry it'd be a great way to lead into the discovery of Harry's true fate (maybe Harry was onto whatever Matthews was doing at the time, but couldn't bring dexter into it until Harry had proof to fit the code yet?). I'm just spitballing here though.
And I always thought Matthews was a crook from the get go. And it'd be a nice way to bring the series to a close with Dexter coming to realize Harry did accept him for who he was and what he became and it would reinforce Dexter paternal relationship with Harrison whether Harrison has a dark passenger or not.
Eta: It'd also reunify Dexter and Debs relationship after the fallout of season 7.
This post was edited on 7/1 at 10:08 am