The way his skin look...... He is dead. I notice the unseated shinigami's Giselle use in her skirmished with Mayuri didn't have their skin like that which means they are still alive but don't have any control of their body's, yes you have to kill a Quincy to zombified them or they should be dead to be zombified, that's for Bambietta case but look at her skin and look at Toshiro, then look at the unseated shinigami's she summon, most importantly their skin color. Bambietta basterbine and toshiro Hitsugaya both have the same skin color, and Bambietta is dead so that means Toshiro is dead also. Giselle did stated she only have to get her blood on a shinigami even if they are alive to controlled them, they will still look regular but they are being controlled. If a shinigami is alive but get Giselle blood on them, they will be zombified and control but they will still look normal, but if they died, they will be controlled anyway , but the noticeable difference is skin color, if their skin is dark like Bambietta = Dead, if not = alive but controlled, get what I'm saying? Toshiro did not look regular like the shinigami's Giselle summon, he look like Bambietta, which means = Decease.