I’m sure the band will want royalties. If you are going to submit the movie to festivals, the possibility of you selling it is certainly a factor. Sound boards are free, I know. But for the quality you are going to need for a movie, they may not be suitable. You know, you could always call them and ask. I believe their offices are in San Rafael CA. I wouldnt be surprised if they just told you to go for it. Better to know for sure than take chances.