Kiba wins either scenario. His speed is simply too overwhelming for Sakura and he will simply split her in half with his three headed dog form. We saw how that thing was able to plow through Juubi clones like it was nothing . Katsuyu is irrelevant because Kiba in his three headed dog form can simply avoid her one and only attack, the acid attack which even Manda was able to avoid, and aim for Sakura, who would then get shredded in half. and there is no way Sakura is dodging that attack when she couldn't even avoid Kabuto's flying buttocks.