How come you have been trusted that random guy who whisper you. If the friend of OP had any sense and not listen to that stranger because probably that guy spy from other opponents and might wanted to fall in the trap and when having a bet.
Just focus your own bet, don't be distracted people around you you will not know who are they. And it should have a lookout behind you to prevent a scenario like that.
That could be true, but if he believes that guy was telling right especially if that guy can explain why he whisper us and said we should choose and follow him, I think he can follow the advice from that guy. But maybe that guy only wants to make us stress to select the right team, and that will happens if we don't have reliable info about the teams. Once we are too stressful, I think we need to leave it and don't choose any of the teams because we cannot focus on what we want to select.