If you manage to find a legitimate (or questionable) NSP of this specific pack, here is the loot table you would unlock. Note: Because this is a live-service game, much of the content requires an online connection to Gameloft’s servers. An offline NSP may only give you the base roster.
: Special outfits and kart skins for all six included racers. Exclusive Customizations Disney Speedstorm -NSP--Ultimate Founder-s Pack...