Locke lands in Tunisia, being watched by camera

After Locke turns the frozen donkey wheel, he exits the island and ends up in Tunisia just like Ben did. Locke also threw up just after arriving in Tunisia just like Ben did. It's not surprising, but it seems that leaving the island puts a strain on the body seeing as both Ben and Locke threw up. Locke's leg is still injured and he's in a lot of pain. He tries to stand up but can't. He notices a camera perched on a post with the wire running across the desert connected by occasional telephone poles. Locke screams for help towards the camera, hoping someone will come help him.

The camera and the telephone poles are new additions since Ben left the island. How did Charles Widmore learn where the island's sends people when they leave or did he already know but somehow knew to expect Locke or someone to show up there? Also, does this mean that the two guys on horses who approached Ben in "The Shape of Things to Come" knew about that spot in the desert too? If so, who did they work for?