Well, Moxie increases the user's Attack one stage upon fainting an opponent, whereas Intimidate lower's the Attack of all opponents by one stage when the ability-bearer switches in. Also, when a Pokémon with Intimidate is your Lead Pokémon in your party, wild Pokémon are 50% less likely to be lower level.
If you are going for Moxie, keep in mind that Krokorok's Attack stat is 82. When it knocks out an opponent, it's Attack stat will be 1.5x the original amount. But, if you are leaning towards Intimidate, your opponent's Attack stat will be 0.66x the original amount.
a picture of the stat modifiers chart is found here.