I can’t imagine both of them would turn down a Rolex endorsement...
Not sure about that nadals. Look at Venus and Serena's initial history, when they first came on to the tennis scene. They were too controversial. Their attitude did not go down well with the white establishment. Serena's tendency to have some on court outbursts, which was perceived as a negative. Their Dad's controversial statements. The white boys in the boardrooms tend to bypass anything that might tarnish their genteel image at Rolex. I think therein lies your answer.
Afterall, who the hell cannafford a million dollar watch??