That is the million dollar question. Maybe this guy's group captured (or just includes)... what's his name from the first episode?
I don't think so. Morgan would have just come up and greeted them himself. He would know that Rick wouldn't trust someone he sent. Morgan was also a ways behind them before. When he found the Termites camp site, everything was aged a few weeks at least if not more.
I have a feeling this guy is with a group that will turn out not to be very nice. They said on the Talking Dead that things were gonna get worse for the group and the next episode preview scenes were not very shiny and happy.