Thanks for trying it out. It’s been a while but I’m sure the test checks for a 404 so if those pages gave a 404 they won’t be recognized as a false positive. I tried leaving some text about possible false positives because some people told me it can make others panic if they don’t really understand web dev well.
Most sites I sent to it came back with plenty of false positives, mainly because htaccess rewrites resolve the URIs as query string IDs and returned empty pages with "Sorry, but the information you're looking for doesn't exist..."