Pielorinho
Iron Fist of Pelor
No; nor does the text suggest that if the fireball is targeted in an especially obvious manner, the victims receive a bonus on their savesInfiniti2000 said:I'll answer with a question...can you use any skill to increase the DC of any other spell? Can you bluff someone into not dodging a fireball as well?

Given that the action type is "varies" and that this particular usage isn't covered specifically, I think you're incorrect on saying that it'd be a standard action: instead, it'd be part of the free action of speaking during combat (assuming it was attempted in combat). There's a strong case that Diplomacy would need to be at least a full-round action, however.If the answer is no, then I'd also say no. Otherwise, you need to consider raising the level of suggestion. On the other hand, using a bluff check would be (at least) a standard action of its own, so to combine it would suggestion would require two rounds or a quickened suggestion*.
Daniel