Did you ask the person who was "disposed of" what he/she wants?
Reality check: while that just plain sucks and the *extra special* people who did it deserve to be beaten, it is hardly uncommon. Nor is it likely to get them anywhere. Precious few bands, even ones that appear to the fans to be quite successful, can even make a living at music, much less get wealthy. Without knowing the specifics, I'd say that exposing the theifs would shock few, create little or no sensation and likely not be worth the effort.
Since you know what I don't, you should go with your gut and do what you think is best, but be sure to check with the injured party first. You don't know what is going on in their life or how this may affect them if you don't ask.