A pH of 3.8 cannot be ignored or you will have all sorts of paste/texture defects. If you do nothing and simply put the dried fruit into the curds, the blueberries will create a localized acidity problem as they rehydrate in the cheese. This will manifest itself as a drier, crumbly area surrounding the fruit. FYI - the same thing happens with tomatoes. This is even more problematic with a Swiss, because Propionic really doesn't like too much acid.
If mitigating with just water, you will have to do that several time to see much effect. By then all of the flavor will be gone. Remember that the acid is IN the berries, not ON the berries. So, I rehydrate with a little baking soda and balance to a pH of 5.4. The blueberries will lose the excess acid, but also some of the natural tartness. They will seem much sweeter because of the increased pH.
There are trade offs, no matter what you do, but the baking soda wash has produced the best results for me.