None of those animals became infected or sick from it. This is one of the largest studies even undertaken to determine the host range of an animal virus. The 1000 rabbit infective dose is very small. So small in fact that it was below the immunogenic threshold of all 28 species with the possible exception of mice which were said to have detectable antibodies. This may have been a large study but it was a very weak study in terms of actually challenging the host non specificity of the virus.
Tenuous evidence suggests the virus originated in rabbits.
More conventional treatment of the epidemiologic data starting with the China outbreaks suggest a non European rabbit origin and a non rabbit origin. Time would be well spent in attempts to identify one or more reservoir species for the RHD virus. There are no guarantees in biology. All viruses mutate, that is normal, but mutations rarely have any effect on the way the virus behaves. New serotypes emerge, new host species become infected, new tissue tropisms form.