I’ve got 98%, although I was so sure I’d gotten everything right. There doesn’t seem to be a way to check, though.
Will I ever know where I went wrong, or if I just failed to click ‘submit’ when I corrected one of my answers?
We can’t help answer that, but you can try contacting the support email (support@freecodecamp.org) to ask them if they have a way to report that back to you.