Multiple sources at Rocksteady tell me that Kevin Conroy recorded dialogue for Suicide Squad Kill the Justice League's post-launch campaign before his passing.
Batman returns to Metropolis in Suicide Squad's upcoming 4th season, after being rescued from a medieval-themed Elseworld of supervillain Brainiac's design, joining The Flash and Green Lantern as the Justice League continues to reform following the events of the game's campaign.
Season 4 of Suicide Squad Kill the Justice League is currently slated to commence in January, 2025. The season also brings Deathstroke into the fray as a new playable character, who is of two minds about rescuing the man who humiliated him in 2015's Arkham Knight.
This storyline concludes in the game's 5th season, when the reassembled Justice League join forces with ARGUS to end Brainiac's multiversal reign of terror. Sources tell me that this will likely serve as the game's finale, with the recent season 1 doing little to reignite sales.