if there are still turns left in the half, then continue playing as if a drive has just ended.If the opponent cannot put 3 on the pitch then he can concede without further penalty.
p15 lbr 6 states what happens when you have a cleared pitch.
the extra rules state that you can forfiet if you can set up less then 3 players, but without any further penalties. It also does not state you should be awarded a td. so its a bit of both but neither completely?