I thought I read an article about him collapsing after getting off the ride, but I can't find anything that supports that now. Skimming through available articles, there's not much as to whether or not he had a preexisting condition. Although, if one of the scareactors got him, I could see it...
Signage is cheap. If slapping up copies of the warnings in some of the most common languages makes people more comfortable, I'm happy as long as it's remains appropriate themed/styled to match the existing signs.
Although correct me if I'm wrong - both the app and the in-park maps offer the various languages, correct? Plus, I've seen many a team member fluent in Spanish - signage or no, there are plenty of ways to verify warnings.