I think there was definitely implicit bias from the houseguests based on their comments. But technically all of their game moves can't directly be related to racism.
I get what you're saying about CBS putting all three at once, but I honestly think it'd be much worse had they not done that in fear of how it looks. If CBS was planning to put all three on at the same time, then I give them credit for doing it for no matter who it was. If we all want to live in a world where color of skin doesn't matter, then shouldn't we just be watching this not caring what combo of people are on at the same time?
Don't get me wrong, CBS has definitely been in the wrong on the racism issue during this show. Often times when Jack starts a rant, they cut feeds to protect him when they should let his true nature show 100%.