I really don't know what DC do now. I mean clearly all that matters is money and this may still do well at the box office, but one terribly reviewed film is bad luck but two is starting to look like a pattern. If they need to double down on batman then fine... The animated films and universe has been shoehorning batman in for years and that seems to work.
Transformers - 57% Rotten
Transformers: Revenge of the Fallen - 19% Rotten
Transformers: Dark of the Moon - 35% Rotten
Transformers: Age of Extinction - 18% Rotten
Still to come from the Transformers Cinematic Universe:
Transformers: The Last Knight
Transformers: Bumblebee's Final Stand
Transformers: Sixth Bay Avenue
Transformers: The Search of Infinite Yuan
DC doesn't have to do anything. They just have to believe in themselves like Michael Bay and Paramount does.