It’s important to remember that there’s a reason that Warner Bros. and DC Films chose Joss Whedon, out of all the directors in Hollywood, to see Justice League to the finish line.
If he says there’s an issue, then there’s probably an issue, and one would imagine that the necessary steps would be taken.
If they aren’t going to listen to his advice, then why have him on board in the first place?
If anyone can have the right insight into Justice League, it’s him.