Five people were all easily within ear shot of Hughes voice but only one person heard a racial slur. You can believe that one person Brandon Phillips who obviously was holding a grudge against Hughes if you wish or you can believe the other four who heard the same thing but don't have a grudge to hold against Hughes. I choose to believe the four who had no axe to grind.
The Pirates interviewed the Reds to see if anyone heard racial slurs. I have a hard time believing had Billy Hatcher who was likely standing within fifteen feet of Phillips heard a racial slur he would not have spoken up to the Pirates or at the very least the media by now.
I think we have gone as far on this as needed.