Possibly, but I can't imagine a writer taking that kind of chance at the height of the Cold War just for verisimilitude.

I mean, the way I imagine it is he chatted with one ore more guys and after a while he got bits here and there he was technically not supposed to have, not enough of its own, but with imagination enough to get the rough picture of how it worked and got very close. But I don't think conscious braking of classified information happened. More carelessness I guess.