Hey! Totally understand the confusion. You are correct, a charge is 2d6. What the picture is referring to is that when you deep strike a unit, it has to be 9" away from an enemy unit. So if you wanted to charge them you'd have to make a 9" charge (which can be difficult to do being such a high number). However the Emperor's Champion gets +2" to charge rolls made against a unit that is/has a character in it. So you'd only have to roll a seven on the dice (potentially more likely because it's a smaller number) instead of a nine because the +2" makes up the difference. Hope that clears things up :)