User blog comment:FairyRaven/Fairy Tail Chapter 397: Steel, Review and Commentary/@comment-5894890-20140826001157/@comment-7418318-20140826080002

Keep in mind that Toshiro isn't really himself. It's quite possible that being turned into a zombie greatly reduces his mental abilities.

Frankly I thought that Z was controlling his zombies directly like pupets until the current chapter.