Flappy, what you can do for a Baton Pass team is use Jolteon. Jolteon is overall a lot better at passing substitutes and it can also take advantage of Thunder, which is 100% accuracy in rain. The reason I say Jolteon is because
a) It's a whole lot faster than Vaporeon and gets an advantage from Thunder
b) It adds type coverage.
Try out Jolteon for this spot.
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If that isn't working for you, I'd say don't use the Baton Passer Vaporeon, use the Wish/Standard Wall. In general, it's way superior.