Alright let's start with the basics. Someone who can transform at will is a Skinwalker not a Werewolf. Werewolves only transform on the full moon.

I'm not sure what he would be if was born a wolf and learned to take human form.

Where are you living that public lynching is legal? He's only twenty so this isn't during the Spanish Inquisition.

If his only experience with Humans is an entire city attempting to kill him where exactly did he learn there was good in humans? It seems like a bit of a leap from "About to be killed by humans" to "Defender of the Weak"

I think you might have the wrong idea about the DIS. You didn't write much about them but the idea I got from what you did write is that there some sort of extermination squad and only the most lucky Supernatural Creatures make it into there ranks. This is not so. If the DIS' job was to eradicate Supernatural forces they would have crumbled long ago. What they do is keep it manageable, they hunt the destructive forces. They don't have a problem with Werewolves, they have a problem with Werewolves who eat people. You wouldn't have needed to get lucky to get into the DIS or not be killed by them. All you'd need is to secure with them the knowledge that you aren't a risk to humans and pass the physical, psychological and mental entrance exams. If you didn't pass you would be turned away not killed.

Last and least, this is a small one but his name changed about halfway through the Bio from Lorenzo to Angelo.

Overall he isn't a bad character but his Bio needs some major flushing out, at the moment his past doesn't seem consistent and I don't have any idea where his life has been previously.