All things - S7-E17
Other mistake: The surname on the envelope is "Szczesny" (which is of Polish origin and means "Lucky"), so its pronunciation should be something like "shtcheznhy." However, in the subtitles the surname is written as "Szezesny" and pronounced by Scully accordingly. (00:06:30)
Answer: He was being facetious. He doesn't specifically know that information, he was merely giving examples of the types of information he has access to.
I think so too.
lionhead