Likewise, I've known people with incredibly vulnerabilities/issues that managed to pass them. Even if you are a bad person for the job or have heavy disqualifiers, if you're confident and have no anxiety over the test, you still pass. Obviously it's a bit more in-depth than that, but as you said, it doesn't measure honesty, it measures anxiety and other sympathetic reactions that are impossible to tell by themselves if it's honesty or something else.