I disagree with this happening as Suicide Squad did well in the box office. Although there’s been no advertising, a Damien Wayne game could possibly not draw. According to Kotaku, the game didn’t impress management.
There could be a lot of intrigue for a game based on a movie that didn’t impress critics. I do see an issue though, as maybe programming and playtesting the different members of the Suicide Squad didn’t work.
In addition, this isn’t the only Warner Bros-DC game possibly inspired by a film that was canned. Around 8 years ago, the Dark Knight game was canned despite Gary Oldman doing voiceover work for it. They would eventually make the Arkham Asylum series instead.