"Most people experience normal, usually mild reactions that include a sore arm, fever, and body aches."
Except nobody gets the smallpox vaccine.
Yeah, and if you are complaining about the mild immune response caused be an attenuated (or even dead) virus, imagine how worse you would feel when infected by the active pathogen.
This isn't the point. The point is that the ruling said it's "completely safe". Since it's not "completely safe", does this mean I could sue them?
What ruling? Where does it say "completely safe"? It's hard to take you seriously when you're not even correctly identifying the document in question. If anyone is confused, it's you.