I think Ben knew there was a station, but didnt know where it was. And Maybe they only discovered the TV station after Kelvin had died, I dont know, but I think Kelvin was clever enough to know that there were cameras because ben would know about that funny side thing. If kelvin know how to Lockdown he obviously knew about the cameras. ALSO perhaps Ben forgot all about the dharma things until the losties came, thats why he used them, because although it sounds stupid most of the dharma stations are dusty when found. PS. I'm sure Ben doesnt know about Desmond.

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ALEXX.