User blog comment:Xilinoc/Ch. 597 - Winded by the Shadow/@comment-493809-20140919032900/@comment-11051098-20140919222805

Yamamoto could only revive those who were killed by Ryûjin Jakka itself. That said, it wouldn't be a shock if Kubo decides to make Yhwach able to actually revive anyone, regardless of how he killed them.