The fact that it did not take very long to develop an ecosystem on this volcanic rock also undermines the whole idea of millions of years from the get go.
You have your facts wrong. If you read your Origin Of Species you learn of many successful breeding exercises by man that transform crops, flowers, and pigeons in a few generations into all sorts of exotics.
This is a similar situation where man has intervened in natural processes to produce a desired result and in doing so has compressed the time required for natural evolutionary growth.