How do you reunit Bartello and that summoner in story level 5? He is just sitting outside the door, and I really need to get the episode complete. Please someone who knows, help me.

Whoo. If you're already past Chapter 4, it may already be too late. In Chapter 4, you're supposed to use the CommSphere at Kilika Island and Kilika Temple. First, you Commsphere Kilika Island and then watch as Dona gives you a tour. Then, the first time you contact Kilika Temple, you'll talk to Barthello, but then he'll get upset and end up breaking the CommSphere. Later on in Chapter 4, you have to CommSphere Kilka Island again and this time, Dona will send up some balloons with that CommSphere heading toward Kilka Temple. Then, do the CommSphere again and the balloons will land at Kilika Temple. Barthello will have gotten the message, but he'll also end up breaking the CommSphere again and Shinra will make one of his mean, but funny comments.

After that, if you try to CommSphere Kilika again, Shinra will just say it's broken. That means you're done and you should be able to reunite them in Chapter 5 simply by making it to the temple. But if you didn't do all of that, then your only choice is to either reload from a save backup or beat the game and then use New Game Plus to pick up what you missed before.