Most of the goons were taken out and Batman just entered the fray. It didn't need to drag on another 3-6 posts with the big gun on the scene. Also, "Guardian serum that takes control of the user for the organization funding him" wasn't in the approved CS. You gotta run stuff like that by me. Did you even get into who he was working for? You teased Waller in the CS but never actually got into it in-game. 

EDIT: If it was Waller, you would've kinda put me in a corner if I wanted to use the Suicide Squad later on in the story. Especially if you were gonna switch up characters after this arc. Why would she need to inject criminals with nanites to make them do her dirty work if she can just give them Guardian serum and control them from within? If you're trying to do random stuff to add your own twist to the ending you need to run it by me first. 

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