Heat the oven to 350°F. Line three 8-inch round cake pans with parchment paper and lightly coat the sides with neutral oil.
Whisk the cake flour, baking powder, and salt. In a separate bowl, beat the dairy free butter, neutral oil, and granulated sugar for 3 minutes, then beat in the egg whites and whole egg in several additions.
Add the dry ingredients in three additions, alternating with the soy milk in two additions. Mix in the vanilla extract, divide the batter among the pans, and bake for 21 to 25 minutes.
Combine the raspberries, sugar, cornstarch, lemon juice, and water in a saucepan. Cook over medium heat for 6 to 8 minutes, stirring often, until thick and jammy, then cool completely.
Melt the dairy free white chocolate over barely simmering water and let it cool until barely warm. Beat the dairy free butter and powdered sugar until fluffy, then beat in the melted chocolate, soy milk, vanilla extract, and salt.
Pipe a border of white chocolate frosting around the edge of the first cooled layer and spread half the raspberry filling inside. Repeat with the second layer, then add the final cake layer.
Frost the top and sides with the remaining white chocolate frosting. Decorate with fresh raspberries and refrigerate for 30 minutes before slicing.