Theory on Dexter original sin finale

So you would think Miami metro would mention Arron Spencer if he was a child killer. Especially during the BHB killings. So my theory is Dexter gets full evidence it is Aaron Spencer, this is while Aaron Spencer convinces the department it’s the cartel. Dexter gets Aaron Spencer on the kill room, this is where Harry walks in (that famous scene from Dexter)

Harry sees what he has created while Aaron Spencer is dead. Harry can’t take the pressure and ends his life a few days later.

This would be perfect. Maybe you can explain Thomas Matthew’s desire for the captain role on Miami metro and how bad he wanted it. You can dig deeper to find out that Harry told Matthews that Spencer was the child killer before Harry ended his life.

This can explain why Matthews might know and how he respects Dexter in a way since Dexter is the reason Matthews became a captain.

Super far fetched but would explain a lot