Quite an easy achievement, though it may sound stressy.
Pick any "long" song, the already mentioned "Shine" and "Something in the way" will fit as well as "Bohemian Rhapsody" or even "Aqualung", "Bad Medicine", ...
Make sure you pick "Band Mate" as your overdrive-power up and "Runaway Notes" of course.
Now you can start hunting those nasty purple notes by playing the purpe notes it creates on its escape. The easy way - if you have your overdrive built up to about 50% - is: let your bandmate do the job for you. As for he never misses a note, you will catch the runaway note in no-time while only having to look at the adjacent lanes if the note manages to escape the original lane.