what is ironic about the death of Reinhold Zucker?

Zucker's death is ironic because we've actually already been made aware that he would be the one to die in the chapter "The Card Player." In this chapter, Death tells us that Hans and Zucker would change places in a few weeks after Zucker loses his cigarettes to Hans in a card game.

Ironically, Death never told us that Zucker would die, only that he would take Han's place because he despised him.