You see, if all 4 or what's left of the town criers claim, then mafia already knows for sure who is the secretary. Sniper has to wait until the criers decide their lynch, then he makes his shot on an unclear. Fact you lynch an unclear and shoot another unclear, hitting secretary at night is 100% in odds.
Thing about hitting secretary is it makes the lynch disabled for town, which in LYLO, that's fatal. So mafia wins the game if all town criers claim with no worries.