Okay, so I just watched this part again, and here's what I think.
Locke knew Ben went to summon Smokey. So Locke went into the jungle and intercepted Smokey, talked to him for a bit, and sent him back. Maybe Locke even asked to have some time with Ben, to work on him, or talk to him, or something. When Locke comes out of the jungle, he knows where Smokey lives, acts impatient, then says they have to find Smokey.
Maybe Locke intervened on Ben's behalf, by talking to him while they were walking through the jungle. Locke got to investigate what Ben might actually be thinking, and it's possible he had some sway with Smokey himself. I don't think Locke is Smokey, or that Smokey manifested himself as Locke, but I wouldn't be surprised if the two had some communication, and Locke was doing some extracurricular activity by taking the time to walk and talk with Ben over to the temple.