I remember this came up before, but I got caught up in a mountain of work and couldn't reply. From memory I had collected up a few examples where people got done for reproducing copyrighted material despite their waivers and disclaimers. I decent lawyer could argue that it is ok to do it, but it doesn't mean that a judge will agree with him!
I may disagree with my own reply above because footballers have image rights and naming rights, but I doubt this falls into it.