So a bunch of procrastination got in the way and I finally decided to unlazy and called upon my fellow ally yesterday to solve this.
It seems that you were really a victim of being in the wrong place at the wrong time, which happens often in this game. At the point security came over to you, it was already known to the HoS about what a vampire was and could do. Considering that, and previous escalation in the round, it isn't exactly outrageous or out of place for them to shoot you like that.
This holds true, as seen in the tickets and the round logs. Also, consider that you were not actually actively talking to security, they had only told you to stop, which can be used as a pretext to really do anything from their side, considering the round situation.
I will close this in 24 hours.