I’m asking myself: why was that scene with Fairbanks included?
Because Gail was seemingly murdered to stop her speaking to him. If AC-12 could find out what he knew that would require her to be killed, then they’d have a massive lead on who is scuppering the murder enquiry and why, and hence where the corruption in MIT leads back to.
As it turns out, his senility (real or exaggerated) meant that the plot could not be resolved via Fairbanks. And therefore we get another two episodes as the plot is able to continue.
Plus it also showed us that Steve is starting to lose control and is heading into erratic behaviour. And that Chloe is a bloody hard grafter who keeps her head down, does what she is asked, and is good at her job.
So the scene was there because it served multiple plot and character-development purposes.
I don’t know why everyone is adamant that Chloe has to be related to every other black person who has ever been on the show. We’ve already had a reveal that Jo is the issue of sibling incest by a notorious gangster. The revelation that Chloe was also a relative of someone else in the programme would ridiculous!