I agree with @Dutchess_III and @Jeruba. I also think that this is the lingering result of the #metoo movement. The movement gave people who were previously hiding in the dark a voice. And sure enough, rape stories strike a chord in those people’s hearts. Those people are now free to be vocal about rape stories and they are quick to side with the victims. They are also supported by society as the result of the movement. So when the accusation turned out to be false, it’s like a rug being pulled under people’s leg, like a plot twist. That added even more attention to the story, as well as some cognitive dissonance among some people. This was also the opportunity for the other people who are just tired of the extremists of the movement to speak out, and I think that’s probably be the reason why the reactions are so divided.
I’m not an American, but I’m speaking as an observant of a similar movement in my country. And in fact, there has been a false rape accusation that also caught people’s attention on the Internet. So there was this father who frantically asked for help with his daughter’s rape case on the Internet because according to him, the authority “didn’t want anything to do with it”. He provided photo evidence an a video showing the girl screaming in pain with wounds all over her body. According to his story, he got involved with some bad people while trying to earn money for the girl’s schooling, and now the people were getting back at him by physically and sexually abusing the girl. The story quickly caught the Internet by storm, and people tried hard to pass the original post around as much as possible so that it would cause enough pressure for the authority to do something. Some people even managed to track down a woman believed to be the mastermind of the crime and spammed her Facebook with insults to eternity. It didn’t help that people started passing sob stories about how the father went through a tragic divorce and how nice the girl was, which further added fuel to the fire.
Then some time later people found out that the entire story was fabricated and they were going around insulting the wrong people all along. And unlike when it was first started, the story quietly died down. There was no apology to the wrongly accused and no one fiercely went after the father like they did with the woman. The last I heard about that story was a passing comment asking how the girl in the video was so convincing. I can see that there is a level of denial among the people, just like with your story. The attitude wasn’t exactly divided, but the story did capture a lot of attention, and it fascinated people so much that they went a great length to dig around for as much information as possible, even fake sob stories.
I’m glad the story never got further away from the Internet though. Things could have been a lot worse for the wrongly accused if it had.