I don’t believe it. You say you spoke with them???? SO you did not witness the ‘one glass’.
Blood alcohol levels do not lie. It is not just the AMOUNT that an individual consumes but a combination of things including how fast you drank; how much you drank; did you take any medication before drinking; when was your previous drink consumed.
Too many people think that they are not incapacitated when indeed they are. The key to uping the believability quotionent on this story is to tell us how tall the person is, how much does the person weigh, how fast they drank the wine, and finally what value showed up on the breathalyzer.
All of the information would allow us to better understand your comment. You have NO idea of how many people end up in front of the judge claiming to have had ‘just one glass of wine’ who blew a .1 or more and even had that value confirmed by a blood draw. Science is not your friend in these situations because the data are the data.