I've no idea, but I wanted to say kudos to you for trying and looking for help. My socially awkward ass would probably chalk it up to a loss and never initiate with the guy again.
About the only thing I can offer is I've sort of been that guy. Had a friend who would have game nights every so often where he'd invite a bunch of people over. I'd almost never go or respond, but damn if I didn't appreciate the hell out of always getting the invite.