Well, there is a mission_lost event, but I don't know if it fires in vs.
I would just loop through the survivors checking their status on round_end, here's a function to do that.
Remember that round_end fires multiple times, it's not necessarily only when the score screen pops up, it seems to fire twice in between round 1 and round 2 on a map.
PHP Code:
public AreAllSurvivorsDead()
{
new IncapOffset = GetEntSendPropOffs("CTerrorPlayer", "m_isIncapacitated");
for (new i=1;i<MaxClients;i++)
if (IsClientInGame(i) && GetClientTeam(i) == 2 && IsPlayerAlive(i) && GetEntData(i, IncapOffset) == 0)
return false;
return true;
}
And the scripting forum is for questions, this is for posting code etc. ;)