Answer: No
Shopify’s main platform works so that only a product can be added to the cart - therefore, Bundle Builder works around this by creating a proxy pseudo-product to represent the complete bundle. This is what we can see in the Cart and under Order Details for a Single SKU Bundle.
However, Multiple SKU Bundles replace the proxy pseudo-product bundle with the real Shopify products (and their respective SKUs) at the checkout stage. Therefore, assigning a replacement SKU would be considered redundant.