Contrary to the Filkovsky's article, diversity, in my opinion, does not disprove the existence of laws of evolution, neither deterministic, nor probabilistic, nor in the form of the trees of possibilities.
Believers in deterministic laws of evolution can claim that the starting points in different regions of the globe were different, the initial systems were different, the available materials were different, the surrounding conditions to which the systems had to adapt were different, etc. That is why it resulted in a diversity.
Believers in stochastic laws of evolution will be unfazed by the fact of diversity at all. To them diversity is an unavoidable outcome of the stochastic nature of the laws.
The same holds for laws of evolution in the form of trees (or even meshes) of possibilities.