Kim did NOT say no. Kim expressed concern about coming in between such a strong, dynamic fanbase. Guza and Steve were both fine with the idea. Kim came back to do it but she was worried. She expressed those worries to Brian Frons who agreed with her. He loved KMc and he loved KeMo and he said you know, let's go another way with this. At the same time, the long-time friendship between Guza and Pratt had cooled off, considerably. Chuck wrote a treatment for a different story for Robin. One that was based loosely on Grey's Anatomy which was, at that time, knocking the top off television ratings. Pratt passed it on to Frons who liked it and said let's do this instead. Guza was so mad he almost blew a gasket and that's why we had Jason making it clear he would sacrifice Robin's life for Sam's during the virus epidemic, and that's why we had Robin standing outside Patrick's hotel room while Patrick and Carly were making out on the bed inside and that's why we had Patrick sleeping the nurse in the shower at the hospital. I forget her name. He hated Scrubs because it wasn't his plan and he hated Scrubs because it was Pratt's plan and the only reason we got a good story is because Frons knew how to exert power. People hated Frons and to be honest he deserved a lot of their wrath, but he is responsible for Scrubs.