The official cast list for Suicide Squad seems to confirm our theory on the REAL villain of the movie - and the actor playing them.
Suicide Squad: Kill The Justice League Includes References To Arkham Origin
Suicide Squad: Kill the Justice League review — Dead on arrival?
Suicide Squad: Villains & Backstory Explained
Suicide Squad: Kill the Justice League will add an offline story mode : r/XboxSeriesX
Suicide Squad: Villains & Backstory Explained
Suicide Squad: Kill the Justice League - Wikipedia
DC Comics Relaunches Suicide Squad With Injustice: Gods Among Us Creative Team - IGN
Suicide Squad: Kill the Justice League: Everything we know
Does Batman die in Suicide Squad: Kill the Justice League? - Polygon
Suicide Squad: Kill the Justice League gets a May release date and reveals evil Batman
Suicide Squad: Kill The Justice League - Every Confirmed Character