While a rabies virus can not survive long outside of its host, it exists in high numbers in the saliva of an infected animal. The host animal being well hydrated is not going to kill the virus, and it is ridiculous to assume the virus "inflicts its host with a paralyzing fear of water". The phenomena of hydrophobia sometimes observed during advanced rabies infection is thought to be related to painful throat spasms and difficulty swallowing.
You can not isolate virus by placing a test tube of blood in a centrifuge. Viruses can be isolated by using a differential gradient gel with an ultracentrifuge.
It requires an electron microscope to determine whether a pellet contains virus, but Hubert seems to be able to tell whether they isolated the virus or not with his naked eye.