If we wanna talk probability 7 players alive, 3/7 are mafia if we wanna talk odds a VT would only 100% clear themselves 3/6 odds (50%), with no counterclaim on doc the VT could pretty safely get to your 3/5 (60%). Although if they consider the outstanding VT claims including yours (even with it leaving 1 liar in the pool) then it becomes nyte and brendan 2/2. If you were going to wager even with incomplete information, you would seriously consider it unlikely all 3 mafia would claim VT day 1. No need to flip coins or roll dice.