I can accept one monkey that is someone's pet and is trained to perform certain duties. There is nothing far fetched about that, it happens in real life all the time. I will roll with that. I cannot accept Mutt becoming the king of the monkeys, swinging across vines leading an army of monkeys into battle against Russians. I cannot accept that the monkeys can differentiate between Spalko driving a car and Indy driving a car and knowing which one is good and which one is evil. So there, I am rolling with a plausible monkey scenario in Raiders and not rolling with an impossible scenario in Skull.