Well Ash's "Vintage" is Pikachu, and I for one do not want Ash to only use Pikachu (well quite frankly I don't want that thing used at all). Honestly A Magikarp with just splash is better than using Pikachu.
I have doubts Throh's trainer will be in the finals, however. Sure he looks important, but then again it could be because he was last year's Donamaite tournament winner, and we've seen champions of something lose in the first round of the tournament.
And also because I think Throh's trainer being in the finals significantly lowers Bianca's chances to be in the finals. I don't expect Ash, Iris or Cilan to reach the finals, especially if Throh's Trainer is to make it far along with Bianca.
Also if that does happen, I have to question the whole point of this tournament. I means sure its great Bianca is a threat, it's also fabulous that Scraggy is being used in official battles. But is making Bianca a competent rival, really the end game for the Donamite? Especially if means making Trip look even more pathetic.