The number of permutations on that would be very large - you'd better high level it. Generate 4 3 bit numbers - each corresponding to a button (A, B, X, Y, L, R + 2 extra repetitions), and then print the corresponding button in the text. You'll also have to check for that exact same button in from the text for the trigger.
I'm against this idea because of, well, why? Introducing more RNG for that small portion doesn't really contribute to anything. But if you do it, it's best you do it well.