I would love to know the actual deal which happened however I highly doubt if he would publish it.
It is very clear to me that redis is a labor of love for antirez and money is not a driving factor anymore in his life. I am sure If it was about money, he would have started something like redis labs long time ago himself.
Personally, if I was as smart as him and created a great open source product like Redis, I would have definitely started something like Redis Labs to benefit from it financially. I am jealous of folks for whom money is not a driving factor.