Found this interview revealing the actors of the Unnamed Criminals in Days Gone Bye, which also features some very interesting trivia on the Criminal that shot Rick.

With all these new character pages being created (like the Woodbury guards) with the actors being unknown, I've been trying to discover their identites on my own. Contact me if you want to help me identify the actors of these characters, and maybe we could interview them like I did with some of the National Guard.