The game will not be called until all threats to the Mafia have been eliminated. At 3:3, if the Town has a way to kill the Mafia there could still be a tie. So the game would not be called until there is nothing that can prevent a Mafia victory. A wincon does not need to explicitly cover every single permutation when a simple "eliminate all threats" covers it adequately.
in this wincon mafia can lose 2 town - 3 mafia scenario if its entering into the night and one of the 2 townies has a 2x busdriver. in the other wincons mafia wud auto win by this point. its unusual to see a townie able to hold mafia from winning. normally that's reserved for the hostile indie if the wincon says eliminate all hostile indies and attain vote majority/parity with town