There’s a lot more going on here than just ITT.
Being an at-will state they can be fired and not much they can do.
Till the owner couldn't keep his story straight. With the conflicting stories put out, they is legal room for them to go after them. It's why companies normally don't comment on the WHY of someone being fired, because they will often get in more trouble from that.
At will doesn't help against discrimination lawsuits, in which case they outright said because it was a black woman they denied and the employees were white is the reasoning for their firing,