Why is Dawkins afraid to debate with William Lane Craig?

It is common knowledge that Richard Dawkins has avoided debating with the philosopher, William Lane Craig. You can see his excuse here.

Dawkins says he won't debate with William Lane Craig because he is a professional debater and creationist.

In fact, Craig is a well-known professional philosopher, who is sceptical of what he calls Neo-Darwinism (which is a philosophical, rather than scientific, worldview generally propounded by people like Dawkins, who are not professional philosophers). The term 'creationist' used to refer to someone who believed in the literal truth of the Genesis 1 account, and rejected any compatibility with a theory of evolution. In Dawkins' world of equivocation, it appears to mean anyone who thinks God has anything to do with the origins of the universe. This of course would mean that a large number of the world's greatest scientists were/are creationists.