Super-simple, IMO. “Hey (ghostee) - we met a while back at (conference), and I saw you posted a role that I would love to chat with you about”. They ghost you?

Super-simple, IMO. “Hey (ghostee) - we met a while back at (conference), and I saw you posted a role that I would love to chat with you about”. They ghost you? Cant take offense at that. They respond? You all are off to the races. Don’t overthink this.