There’s conflicting reports. Some have said execs who saw Batgirl called it “irredeemable”. So they thought it was so bad that they were unwilling to dump another $20-30 million to fix all the problems and to have it still potentially bomb.
If Flash comes out I can definitely see them changing the ending. Keaton will not be the DCEU Batman going forward and Supergirl will not replace Superman.
Different people running those studios. This whole thing is pretty unprecedented.