Plankton's Robotic Revenge Cheat Menu?

So I got Plankton's Robot Revenge recently for my Wii U and found a cheat menu within the Options with what seems to be 6 available cheats that are just "???". The problem I am having though is that nobody anywhere online seems to know what they are either! So after much searching and disappointment I have turned to SBmania for help because I knew if you guys didn't know what they were neither does anyone else! SO I BEG! Can anyone tell me or show me where I can find these "infamous" 6 cheats?

"I'm begging you!" - Spongebob Squarepants

Like other games, it appears to be one of those "do this thing in the game and you unlock a cheat." But it's not! So I've beaten the game with all 5 characters, upgraded all their weapons to their max and no cheats pop up! If anyone knows how to make them come up, please tell me!

Okay, I've completed Plankton's Robotic Revenge, unlocked all the weapons for every character, and upgraded them! (Patrick's voice clips... Wow)
No cheats still...
I am on 3DS version if that helps though!

Maybe there is some sort of secret area in one of the levels or something? Idk!

There are a large amount of areas that would be very hard to reach. I have only played this game by myself, so I would not know if it has to do with multiplayer or not.