If Matt Walsh had seriously misrepresented anyone, then they could just say so.
If he had somehow used editing tricks to falsely misrepresent them (1) as claiming that trans-women are women, (2) not being able to coherently explain what a woman is, then they could all come out and make a fuss that would get picked up by parts of the media. They could all be saying, "actually this is my definition of woman and doesn't it make wonderful sense".
If you want to argue that, sure, they couldn't explain what a woman is, but Matt Walsh didn't treat them the same way, and used editing to make them look an extra 20% stupid, then it's a relatively minor criticism. It may show a lack of integrity on the part of Matt Walsh as a documentary maker, but his basic point would still be correct.
I point again to the Dr. Phil episode. Matt Walsh didn't control the editing for that. But in a similar way, he made his opponents look stupid. You don't need editing to make the trans activist side look stupid!
And it's difficult to take seriously the, "you have a closed mind" stuff, given that the trans-activist side will openly say, "no debate" and try to shut down talks on the subject. They openly admit to having a closed mind! Are any GC feminists or conservatives trying to shut down debate on this subject? I don't mean indoctrinating children, I mean debate in the adult world.