I know it's only an idea, but anyway, Kurono wasn't part of the team back in the days, otherwise Izumi and Nishi would remember him. Nishi would have no reason to refrain from talking to Kurono about old times if he knew him. Also there's Nishi's journal. It's interesting that he might've decided to start it after he got all alone, or maybe Kurono is a dumbass and didn't see Izumi's name on it. On the purpose of the train station Suzuki scene and the comparison with the first chapter, nice, but probably as already pointed, should be just to emphasize the idea of gratitude and make us question whether Kurono told the Old Man the right info or if he was a prick again ^^.