Dr Pepper wrote: She did know it. She told Parson and he called Jack and addressed him by it.
But it's quite certain that Stanley, at least can't see names. Remember his little ploy with Zhoppa.
So perhaps there's more than one level of the See Stats ability. And Parson's glasses have Greater See Stats.
Only Wanda knew it. And to our knowledge she never told Parson Jack's last name.
I'm thinking Parson could have solved the problem by looking with his glasses, and just didn't know it, as nobody did.