Board Thread:Manga Discussion/@comment-34005353-20180130135414/@comment-33806992-20180511233138

I think the big issue here is this:  Kira doesn't know he only has to last out for 6 minutes. Only Hayato knows precisely what happened between time loops, and the only thing Kira was able to infer based on Hayato's reaction was that Rohan would die soon.

Sure, as you say, he can safely assume that Josuke HAS been bombed, but he would have to gamble on when, precisely, the bombing took place. If more than just a few minutes needed to pass before he won, then the chances of his surviving without his stand until the bombs went off were too low to be worth risking his life on.