He's not going to die, he is in company of a healer who learned things from the best healer in her home world. It's more like a coma or something, not dying, not that people can't die from those but ... He is just sleeping. A lot. And more reasons why I am glad, that I wasn't in Harrogate -- which sounds more like Harrohell -- check, or if I hadn't had visions there, that would have been ironic with how much I've had them back home about things. [ in other words, that was one hell of a weather report! ]

No, pretty sure I would have noticed poisoning and besides I could cure it... And can't think of anyone else than maybe himself who'd want to do that? [Sure, Eren could punch him sometimes but he wouldn't want Jean to sleep forever and the last thing she knows about them meeting, it was total opposites of punching or even being angry.]