Because Katz said he paid her himself - he admitted paying her after the allegations came out. If he had given it through the company, he'd have said as much and would have immediately reduced suspicion.
Suspicion? For what? These were not public comments. I do say these texts were creepy and I did initially call for Katz to sell the team unless this could be explained. Now I believe we cannot assume too much until we know more for the following reasons
1. The texts could make sense from the point of view of Katz being the decision maker of a company trying to secure talent.
2. The woman denies there was any sexual relationship between them and this was about work. Initially I thought this was a story about a woman suing Katz for abusing his power imbalance. That isn't the truth but it is the understandable first impression that everyone takes away.
3. The texts are not from a phone. They are images from the couple that the woman is suing for rape, and this is part of a strategy to smear her. These could have been doctored. Although, even though Katz's people say they were doctored we haven't heard that from the woman. But still, we do not have texts. We have an image of texts. That is the only evidence that has sunk Katz here unless we include the word of that couple.
This thread has become a hamster wheel of people coming in thinking this story is something different, just like my false first impression. It's been explained over and over