A lot of people have conjectured that the man seen in the Pearl moniters was Radzinsky, which would make Kelvin a (bigger) liar. I think this would be a relatively good theory, except that it is now officially refuted by Gregg Nations, who is part of LOST’s writing and production team (he also confirms that Radzinsky is dead).
Read his post answering a fan question on The Fuselage.
Eyepatch guy is probably the owner of the glass eye found in the Arrow bunker. It is interesting that on close-ups, this man is wearing a DHARMA-logoed jumpsuit, so he appears to be a DHARMA employee. He is played by actor Andrew Divoff, who has not acted on LOST before, and appears to often play villains.
Who do you think the ‘one-eyed’ guy is?