I mean... you're completely right and some of the stuff is as ridiculous as you're suggesting (e.g. the furniture). However... what we're agreeing on is that the fungus is absorbing alpha/beta particles and gamma rays that are coming off the radioactive material, which in theory should mean that it would act as a radiation shield. Whether it's a more effective radiation shield than other options is the big question, and for space travel in particular the question I'd want to know is how effective is a given mass of this fungus relative to other options (e.g. water).

Id like to know about its failure modes. Does the fungus die when kept in less than ideal conditions? How quickly?