The first sentence is convoluted. You aren't lying if you don't say something. The second sentence is fine. In the second series of sentences, both are possible but the first option is awkward. You would normally put "while watching a football game" as a modifier to "he won't move." Meaning, you need to put the final clause in front of "in case of fire" : "He won't move while watching a football game, even in case of fire." The second sentence is correct; changing "in case of" to "if there is" allows the clauses to be reversed.

In the first scenario, the first option doesn’t work as well as the second because you’re not really lying if you don’t say anything. You can pretty much use the two in the second scenario interchangeably.