Who knows. Even people only temporarily in a place may run into something that could be important, maybe just because they then could personally testify seeing or hearing it, even if that would be decades later. Okay, I sometimes write fiction as a hobby so I can think up of all kind of scenarios at the drop of a hat, but

• he is looking for something else, finds papers he reads through because he gets curious, there is something in them

• he is told something by somebody who has worked there long

• he makes friends with somebody there who knows something, tells him about it later and is now maybe willing to become a whistleblower

And so on. Again, the connection may signify something, no way to know. Or it may not.