I was going to say the same thing - if he works and has friends, his social anxiety is at least not severe. also, I think he might just be getting all of his baggage out there in the open so you know ahead of time.

I would meet him if I were you. he even built in an easy-out for you by saying he's open to just being friends. at the very least, it's helpful to have a friend that understands social anxiety.