You’re quite the gambler! You breed barred rock hens to a Rhode Island Red rooster to get the BSL hybrid. That rooster is where the gold/red leakage comes from. So, that’s my theory on your little chicken.
White/yellow… I bet he was put in a batch of all female black sex links by mistake. I’m not trying to insult your intelligence by no means, but do you know how to breed to get a black sex link?
I could easily be wrong, but as soon as I saw your description with the pic, those cockerels were the first thing I thought of. I sold several as chicks but we kept 4 up until 4 months old. I even named them the Quad City DJs. They were the ugliest birds I’ve ever had. The leakage was bad!