This is almost 2 years after the original posting, but being a process server myself, I find it as hard to believe someone was "attacked" by one, as I would if someone said they were attacked by their pizza delivery driver. Many people getting served are in desperate situations, and maybe their last attempt at a way out of their problems, is to make up that they were attacked and hopefully sue for damages.
Granted there are psychos out there in any profession, but any server who conducted their business violently (we're the ones who have to worry about being attacked, and not just by humans...sometimes it's by dogs) probably wouldn't last a day at their job.
In any case, by contacting the plantiffs in your case, you could get to the bottom of who the serving company is, and with one click of a button they could find exactly who the server was. I don't know why someone would go to an internet advice site for this...I only came here because I was bored surfing the web for cool server stories, because we have many