When you blatantly tell people that you're protesting, it's no longer silent. When you give people a notification that you're going to do something illegal, then you show up and do it, then that's not really silent. When you're asked to move along, and you don't, then that's illegal. I would also bet dimes to donuts that there's a no loitering sign out front of the hospital as well (given the laws in place), so standing there doing nothing may very well also be illegal. Pretty standard stuff.
No, you have a crime. That's it. I know you want this to be the hill you die on so bad, but you're just incorrect. For someone that gets so granular on other threads it
almost seems like you have some form of bias with this.