If you try to download from the main page it won’t work, because it will try to fetch the newest updates…which aren’t compatible with your OS. That then results in various messages similar to what you’re sharing on that.
The link I provided should have then sent you to https://github.com/brave/brave-browser/releases/tag/v1.57.64 and as the instructions say:
macOS
Brave-Browser-*.dmgorBrave-Browser-*.pkgwill install this version.
I do always hate how they have a variety of files to choose from. I do believe you would use https://github.com/brave/brave-browser/releases/download/v1.57.64/Brave-Browser-x64.dmg
If you just add that on top of your current (don’t uninstall), it should manually update you to the 1.57.64, but I’m still not sure if it would solve your issue…but it would be worth trying.