Hi, 
 I think a bit of 'composition of place' would work well there, providing a picture of the cafeteria. 
 I like the more pared down version (especially as it avoids the back story), but if the narrative eye is going to suddenly shift to another focus, there should be some reason for doing so. Providing a sense of physical context for the conversation can provide that reason, but just showing someone sitting nearby--especially when the shift is so short--doesn't achieve as much as it can.